Calculus Examples

2 {(x^{2} + y^{2})}^{2} = 25 (x^{2} - y^{2})

$2 {(x^{2} + y^{2})}^{2} = 25 (x^{2} - y^{2})$ at

$(3, 1)$

Step 1

Find the first derivative and evaluate at

$x = 3$ and

$y = 1$ to find the slope of the tangent line.

Tap for more steps...

Step 1.1

Differentiate both sides of the equation.

$\frac{d}{d x} (2 {(x^{2} + y^{2})}^{2}) = \frac{d}{d x} (25 (x^{2} - y^{2}))$

Step 1.2

Differentiate the left side of the equation.

Tap for more steps...

Step 1.2.1

Since

$2$ is constant with respect to

$x$ , the derivative of

$2 {(x^{2} + y^{2})}^{2}$ with respect to

$x$ is

$2 \frac{d}{d x} [{(x^{2} + y^{2})}^{2}]$ .

$2 \frac{d}{d x} [{(x^{2} + y^{2})}^{2}]$

Step 1.2.2

Differentiate using the chain rule, which states that

$\frac{d}{d x} [f (g (x))]$ is

$f' (g (x)) g' (x)$ where

$f (x) = x^{2}$ and

$g (x) = x^{2} + y^{2}$ .

Tap for more steps...

Step 1.2.2.1

To apply the Chain Rule, set

$u_{1}$ as

$x^{2} + y^{2}$ .

$2 (\frac{d}{d u_{1}} [{u_{1}}^{2}] \frac{d}{d x} [x^{2} + y^{2}])$

Step 1.2.2.2

Differentiate using the Power Rule which states that

$\frac{d}{d u_{1}} [{u_{1}}^{n}]$ is

$n {u_{1}}^{n - 1}$ where

$n = 2$ .

$2 (2 u_{1} \frac{d}{d x} [x^{2} + y^{2}])$

Step 1.2.2.3

Replace all occurrences of

$u_{1}$ with

$x^{2} + y^{2}$ .

$2 (2 (x^{2} + y^{2}) \frac{d}{d x} [x^{2} + y^{2}])$

Step 1.2.3

Differentiate.

Tap for more steps...

Step 1.2.3.1

Multiply

$2$ by

$2$ .

$4 ((x^{2} + y^{2}) \frac{d}{d x} [x^{2} + y^{2}])$

Step 1.2.3.2

By the Sum Rule, the derivative of

$x^{2} + y^{2}$ with respect to

$x$ is

$\frac{d}{d x} [x^{2}] + \frac{d}{d x} [y^{2}]$ .

$4 (x^{2} + y^{2}) (\frac{d}{d x} [x^{2}] + \frac{d}{d x} [y^{2}])$

Step 1.2.3.3

Differentiate using the Power Rule which states that

$\frac{d}{d x} [x^{n}]$ is

$n x^{n - 1}$ where

$n = 2$ .

$4 (x^{2} + y^{2}) (2 x + \frac{d}{d x} [y^{2}])$

Step 1.2.4

Differentiate using the chain rule, which states that

$\frac{d}{d x} [f (g (x))]$ is

$f' (g (x)) g' (x)$ where

$f (x) = x^{2}$ and

$g (x) = y$ .

Tap for more steps...

Step 1.2.4.1

To apply the Chain Rule, set

$u_{2}$ as

$y$ .

$4 (x^{2} + y^{2}) (2 x + \frac{d}{d u_{2}} [{u_{2}}^{2}] \frac{d}{d x} [y])$

Step 1.2.4.2

Differentiate using the Power Rule which states that

$\frac{d}{d u_{2}} [{u_{2}}^{n}]$ is

$n {u_{2}}^{n - 1}$ where

$n = 2$ .

$4 (x^{2} + y^{2}) (2 x + 2 u_{2} \frac{d}{d x} [y])$

Step 1.2.4.3

Replace all occurrences of

$u_{2}$ with

$y$ .

$4 (x^{2} + y^{2}) (2 x + 2 y \frac{d}{d x} [y])$

Step 1.2.5

Rewrite

$\frac{d}{d x} [y]$ as

$y'$ .

$4 (x^{2} + y^{2}) (2 x + 2 y y')$

Step 1.2.6

Simplify.

Tap for more steps...

Step 1.2.6.1

Apply the distributive property.

$(4 x^{2} + 4 y^{2}) (2 x + 2 y y')$

Step 1.2.6.2

Reorder the factors of

$(4 x^{2} + 4 y^{2}) (2 x + 2 y y')$ .

$(2 x + 2 y y') (4 x^{2} + 4 y^{2})$

Step 1.3

Differentiate the right side of the equation.

Tap for more steps...

Step 1.3.1

Differentiate.

Tap for more steps...

Step 1.3.1.1

Since

$25$ is constant with respect to

$x$ , the derivative of

$25 (x^{2} - y^{2})$ with respect to

$x$ is

$25 \frac{d}{d x} [x^{2} - y^{2}]$ .

$25 \frac{d}{d x} [x^{2} - y^{2}]$

Step 1.3.1.2

By the Sum Rule, the derivative of

$x^{2} - y^{2}$ with respect to

$x$ is

$\frac{d}{d x} [x^{2}] + \frac{d}{d x} [- y^{2}]$ .

$25 (\frac{d}{d x} [x^{2}] + \frac{d}{d x} [- y^{2}])$

Step 1.3.1.3

Differentiate using the Power Rule which states that

$\frac{d}{d x} [x^{n}]$ is

$n x^{n - 1}$ where

$n = 2$ .

$25 (2 x + \frac{d}{d x} [- y^{2}])$

Step 1.3.1.4

Since

$- 1$ is constant with respect to

$x$ , the derivative of

$- y^{2}$ with respect to

$x$ is

$- \frac{d}{d x} [y^{2}]$ .

$25 (2 x - \frac{d}{d x} [y^{2}])$

Step 1.3.2

Differentiate using the chain rule, which states that

$\frac{d}{d x} [f (g (x))]$ is

$f' (g (x)) g' (x)$ where

$f (x) = x^{2}$ and

$g (x) = y$ .

Tap for more steps...

Step 1.3.2.1

To apply the Chain Rule, set

$u$ as

$y$ .

$25 (2 x - (\frac{d}{d u} [u^{2}] \frac{d}{d x} [y]))$

Step 1.3.2.2

Differentiate using the Power Rule which states that

$\frac{d}{d u} [u^{n}]$ is

$n u^{n - 1}$ where

$n = 2$ .

$25 (2 x - (2 u \frac{d}{d x} [y]))$

Step 1.3.2.3

Replace all occurrences of

$u$ with

$y$ .

$25 (2 x - (2 y \frac{d}{d x} [y]))$

Step 1.3.3

Multiply

$2$ by

$- 1$ .

$25 (2 x - 2 (y \frac{d}{d x} [y]))$

Step 1.3.4

Rewrite

$\frac{d}{d x} [y]$ as

$y'$ .

$25 (2 x - 2 y y')$

Step 1.3.5

Simplify.

Tap for more steps...

Step 1.3.5.1

Apply the distributive property.

$25 (2 x) + 25 (- 2 y y')$

Step 1.3.5.2

Combine terms.

Tap for more steps...

Step 1.3.5.2.1

Multiply

$2$ by

$25$ .

$50 x + 25 (- 2 y y')$

Step 1.3.5.2.2

Multiply

$- 2$ by

$25$ .

$50 x - 50 y y'$

Step 1.3.5.3

Reorder terms.

$- 50 y y' + 50 x$

Step 1.4

Reform the equation by setting the left side equal to the right side.

$(2 x + 2 y y') (4 x^{2} + 4 y^{2}) = - 50 y y' + 50 x$

Step 1.5

Solve for

$y'$ .

Tap for more steps...

Step 1.5.1

Simplify

$(2 x + 2 y y') (4 x^{2} + 4 y^{2})$ .

Tap for more steps...

Step 1.5.1.1

Rewrite.

$0 + 0 + (2 x + 2 y y') (4 x^{2} + 4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.2

Simplify by adding zeros.

$(2 x + 2 y y') (4 x^{2} + 4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.3

Expand

$(2 x + 2 y y') (4 x^{2} + 4 y^{2})$ using the FOIL Method.

Tap for more steps...

Step 1.5.1.3.1

Apply the distributive property.

$2 x (4 x^{2} + 4 y^{2}) + 2 y y' (4 x^{2} + 4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.3.2

Apply the distributive property.

$2 x (4 x^{2}) + 2 x (4 y^{2}) + 2 y y' (4 x^{2} + 4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.3.3

Apply the distributive property.

$2 x (4 x^{2}) + 2 x (4 y^{2}) + 2 y y' (4 x^{2}) + 2 y y' (4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.4

Simplify each term.

Tap for more steps...

Step 1.5.1.4.1

Rewrite using the commutative property of multiplication.

$2 \cdot 4 x \cdot x^{2} + 2 x (4 y^{2}) + 2 y y' (4 x^{2}) + 2 y y' (4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.4.2

Multiply

$x$ by

$x^{2}$ by adding the exponents.

Tap for more steps...

Step 1.5.1.4.2.1

Move

$x^{2}$ .

$2 \cdot 4 (x^{2} x) + 2 x (4 y^{2}) + 2 y y' (4 x^{2}) + 2 y y' (4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.4.2.2

Multiply

$x^{2}$ by

$x$ .

Tap for more steps...

Step 1.5.1.4.2.2.1

Raise

$x$ to the power of

$1$ .

$2 \cdot 4 (x^{2} x^{1}) + 2 x (4 y^{2}) + 2 y y' (4 x^{2}) + 2 y y' (4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.4.2.2.2

Use the power rule

$a^{m} a^{n} = a^{m + n}$ to combine exponents.

$2 \cdot 4 x^{2 + 1} + 2 x (4 y^{2}) + 2 y y' (4 x^{2}) + 2 y y' (4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.4.2.3

Add

$2$ and

$1$ .

$2 \cdot 4 x^{3} + 2 x (4 y^{2}) + 2 y y' (4 x^{2}) + 2 y y' (4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.4.3

Multiply

$2$ by

$4$ .

$8 x^{3} + 2 x (4 y^{2}) + 2 y y' (4 x^{2}) + 2 y y' (4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.4.4

Rewrite using the commutative property of multiplication.

$8 x^{3} + 2 \cdot 4 x y^{2} + 2 y y' (4 x^{2}) + 2 y y' (4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.4.5

Multiply

$2$ by

$4$ .

$8 x^{3} + 8 x y^{2} + 2 y y' (4 x^{2}) + 2 y y' (4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.4.6

Multiply

$4$ by

$2$ .

$8 x^{3} + 8 x y^{2} + 8 y y' x^{2} + 2 y y' (4 y^{2}) = - 50 y y' + 50 x$

Step 1.5.1.4.7

Multiply

$y$ by

$y^{2}$ by adding the exponents.

Tap for more steps...

Step 1.5.1.4.7.1

Move

$y^{2}$ .

$8 x^{3} + 8 x y^{2} + 8 y y' x^{2} + 2 (y^{2} y) y' \cdot 4 = - 50 y y' + 50 x$

Step 1.5.1.4.7.2

Multiply

$y^{2}$ by

$y$ .

Tap for more steps...

Step 1.5.1.4.7.2.1

Raise

$y$ to the power of

$1$ .

$8 x^{3} + 8 x y^{2} + 8 y y' x^{2} + 2 (y^{2} y^{1}) y' \cdot 4 = - 50 y y' + 50 x$

Step 1.5.1.4.7.2.2

Use the power rule

$a^{m} a^{n} = a^{m + n}$ to combine exponents.

$8 x^{3} + 8 x y^{2} + 8 y y' x^{2} + 2 y^{2 + 1} y' \cdot 4 = - 50 y y' + 50 x$

Step 1.5.1.4.7.3

Add

$2$ and

$1$ .

$8 x^{3} + 8 x y^{2} + 8 y y' x^{2} + 2 y^{3} y' \cdot 4 = - 50 y y' + 50 x$

Step 1.5.1.4.8

Multiply

$4$ by

$2$ .

$8 x^{3} + 8 x y^{2} + 8 y y' x^{2} + 8 y^{3} y' = - 50 y y' + 50 x$

Step 1.5.2

Add

$50 y y'$ to both sides of the equation.

$8 x^{3} + 8 x y^{2} + 8 y y' x^{2} + 8 y^{3} y' + 50 y y' = 50 x$

Step 1.5.3

Move all terms not containing

$y'$ to the right side of the equation.

Tap for more steps...

Step 1.5.3.1

Subtract

$8 x^{3}$ from both sides of the equation.

$8 x y^{2} + 8 y y' x^{2} + 8 y^{3} y' + 50 y y' = 50 x - 8 x^{3}$

Step 1.5.3.2

Subtract

$8 x y^{2}$ from both sides of the equation.

$8 y y' x^{2} + 8 y^{3} y' + 50 y y' = 50 x - 8 x^{3} - 8 x y^{2}$

Step 1.5.4

Factor

$2 y y'$ out of

$8 y y' x^{2} + 8 y^{3} y' + 50 y y'$ .

Tap for more steps...

Step 1.5.4.1

Factor

$2 y y'$ out of

$8 y y' x^{2}$ .

$2 y y' (4 x^{2}) + 8 y^{3} y' + 50 y y' = 50 x - 8 x^{3} - 8 x y^{2}$

Step 1.5.4.2

Factor

$2 y y'$ out of

$8 y^{3} y'$ .

$2 y y' (4 x^{2}) + 2 y y' (4 y^{2}) + 50 y y' = 50 x - 8 x^{3} - 8 x y^{2}$

Step 1.5.4.3

Factor

$2 y y'$ out of

$50 y y'$ .

$2 y y' (4 x^{2}) + 2 y y' (4 y^{2}) + 2 y y' \cdot 25 = 50 x - 8 x^{3} - 8 x y^{2}$

Step 1.5.4.4

Factor

$2 y y'$ out of

$2 y y' (4 x^{2}) + 2 y y' (4 y^{2})$ .

$2 y y' (4 x^{2} + 4 y^{2}) + 2 y y' \cdot 25 = 50 x - 8 x^{3} - 8 x y^{2}$

Step 1.5.4.5

Factor

$2 y y'$ out of

$2 y y' (4 x^{2} + 4 y^{2}) + 2 y y' \cdot 25$ .

$2 y y' (4 x^{2} + 4 y^{2} + 25) = 50 x - 8 x^{3} - 8 x y^{2}$

Step 1.5.5

Divide each term in

$2 y y' (4 x^{2} + 4 y^{2} + 25) = 50 x - 8 x^{3} - 8 x y^{2}$ by

$2 y (4 x^{2} + 4 y^{2} + 25)$ and simplify.

Tap for more steps...

Step 1.5.5.1

Divide each term in

$2 y y' (4 x^{2} + 4 y^{2} + 25) = 50 x - 8 x^{3} - 8 x y^{2}$ by

$2 y (4 x^{2} + 4 y^{2} + 25)$ .

$\frac{2 y y' (4 x^{2} + 4 y^{2} + 25)}{2 y (4 x^{2} + 4 y^{2} + 25)} = \frac{50 x}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x^{3}}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.2

Simplify the left side.

Tap for more steps...

Step 1.5.5.2.1

Cancel the common factor of

$2$ .

Tap for more steps...

Step 1.5.5.2.1.1

Cancel the common factor.

Step 1.5.5.2.1.2

Rewrite the expression.

$\frac{y y' (4 x^{2} + 4 y^{2} + 25)}{y (4 x^{2} + 4 y^{2} + 25)} = \frac{50 x}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x^{3}}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.2.2

Cancel the common factor of

$y$ .

Tap for more steps...

Step 1.5.5.2.2.1

Cancel the common factor.

Step 1.5.5.2.2.2

Rewrite the expression.

$\frac{y' (4 x^{2} + 4 y^{2} + 25)}{4 x^{2} + 4 y^{2} + 25} = \frac{50 x}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x^{3}}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.2.3

Cancel the common factor of

$4 x^{2} + 4 y^{2} + 25$ .

Tap for more steps...

Step 1.5.5.2.3.1

Cancel the common factor.

Step 1.5.5.2.3.2

Divide

$y'$ by

$1$ .

$y' = \frac{50 x}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x^{3}}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3

Simplify the right side.

Tap for more steps...

Step 1.5.5.3.1

Simplify each term.

Tap for more steps...

Step 1.5.5.3.1.1

Cancel the common factor of

$50$ and

$2$ .

Tap for more steps...

Step 1.5.5.3.1.1.1

Factor

$2$ out of

$50 x$ .

$y' = \frac{2 (25 x)}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x^{3}}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.1.2

Cancel the common factors.

Tap for more steps...

Step 1.5.5.3.1.1.2.1

Factor

$2$ out of

$2 y (4 x^{2} + 4 y^{2} + 25)$ .

$y' = \frac{2 (25 x)}{2 (y (4 x^{2} + 4 y^{2} + 25))} + \frac{- 8 x^{3}}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.1.2.2

Cancel the common factor.

$y' = \frac{2 (25 x)}{2 (y (4 x^{2} + 4 y^{2} + 25))} + \frac{- 8 x^{3}}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.1.2.3

Rewrite the expression.

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x^{3}}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.2

Cancel the common factor of

$- 8$ and

$2$ .

Tap for more steps...

Step 1.5.5.3.1.2.1

Factor

$2$ out of

$- 8 x^{3}$ .

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{2 (- 4 x^{3})}{2 y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.2.2

Cancel the common factors.

Tap for more steps...

Step 1.5.5.3.1.2.2.1

Factor

$2$ out of

$2 y (4 x^{2} + 4 y^{2} + 25)$ .

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{2 (- 4 x^{3})}{2 (y (4 x^{2} + 4 y^{2} + 25))} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.2.2.2

Cancel the common factor.

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{2 (- 4 x^{3})}{2 (y (4 x^{2} + 4 y^{2} + 25))} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.2.2.3

Rewrite the expression.

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.3

Move the negative in front of the fraction.

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 8 x y^{2}}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.4

Cancel the common factor of

$- 8$ and

$2$ .

Tap for more steps...

Step 1.5.5.3.1.4.1

Factor

$2$ out of

$- 8 x y^{2}$ .

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{2 (- 4 x y^{2})}{2 y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.4.2

Cancel the common factors.

Tap for more steps...

Step 1.5.5.3.1.4.2.1

Factor

$2$ out of

$2 y (4 x^{2} + 4 y^{2} + 25)$ .

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{2 (- 4 x y^{2})}{2 (y (4 x^{2} + 4 y^{2} + 25))}$

Step 1.5.5.3.1.4.2.2

Cancel the common factor.

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{2 (- 4 x y^{2})}{2 (y (4 x^{2} + 4 y^{2} + 25))}$

Step 1.5.5.3.1.4.2.3

Rewrite the expression.

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 4 x y^{2}}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.5

Cancel the common factor of

$y^{2}$ and

$y$ .

Tap for more steps...

Step 1.5.5.3.1.5.1

Factor

$y$ out of

$- 4 x y^{2}$ .

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{y (- 4 x y)}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.5.2

Cancel the common factors.

Tap for more steps...

Step 1.5.5.3.1.5.2.1

Cancel the common factor.

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{y (- 4 x y)}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.1.5.2.2

Rewrite the expression.

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{- 4 x y}{4 x^{2} + 4 y^{2} + 25}$

Step 1.5.5.3.1.6

Move the negative in front of the fraction.

$y' = \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x y}{4 x^{2} + 4 y^{2} + 25}$

Step 1.5.5.3.2

To write

$- \frac{4 x y}{4 x^{2} + 4 y^{2} + 25}$ as a fraction with a common denominator, multiply by

$\frac{y}{y}$ .

$y' = - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x y}{4 x^{2} + 4 y^{2} + 25} \cdot \frac{y}{y}$

Step 1.5.5.3.3

Write each expression with a common denominator of

$y (4 x^{2} + 4 y^{2} + 25)$ , by multiplying each by an appropriate factor of

$1$ .

Tap for more steps...

Step 1.5.5.3.3.1

Multiply

$\frac{4 x y}{4 x^{2} + 4 y^{2} + 25}$ by

$\frac{y}{y}$ .

$y' = - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x y \cdot y}{(4 x^{2} + 4 y^{2} + 25) y}$

Step 1.5.5.3.3.2

Reorder the factors of

$(4 x^{2} + 4 y^{2} + 25) y$ .

$y' = - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{25 x}{y (4 x^{2} + 4 y^{2} + 25)} - \frac{4 x y \cdot y}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.4

Combine the numerators over the common denominator.

$y' = - \frac{4 x^{3}}{y (4 x^{2} + 4 y^{2} + 25)} + \frac{25 x - 4 x y \cdot y}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.5

Combine the numerators over the common denominator.

$y' = \frac{- 4 x^{3} + 25 x - 4 x y \cdot y}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.6

Multiply

$y$ by

$y$ by adding the exponents.

Tap for more steps...

Step 1.5.5.3.6.1

Move

$y$ .

$y' = \frac{- 4 x^{3} + 25 x - 4 x (y \cdot y)}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.6.2

Multiply

$y$ by

$y$ .

$y' = \frac{- 4 x^{3} + 25 x - 4 x y^{2}}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.7

Factor

$x$ out of

$- 4 x^{3} + 25 x - 4 x y^{2}$ .

Tap for more steps...

Step 1.5.5.3.7.1

Factor

$x$ out of

$- 4 x^{3}$ .

$y' = \frac{x (- 4 x^{2}) + 25 x - 4 x y^{2}}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.7.2

Factor

$x$ out of

$25 x$ .

$y' = \frac{x (- 4 x^{2}) + x \cdot 25 - 4 x y^{2}}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.7.3

Factor

$x$ out of

$- 4 x y^{2}$ .

$y' = \frac{x (- 4 x^{2}) + x \cdot 25 + x (- 4 y^{2})}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.7.4

Factor

$x$ out of

$x (- 4 x^{2}) + x \cdot 25$ .

$y' = \frac{x (- 4 x^{2} + 25) + x (- 4 y^{2})}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.7.5

Factor

$x$ out of

$x (- 4 x^{2} + 25) + x (- 4 y^{2})$ .

$y' = \frac{x (- 4 x^{2} + 25 - 4 y^{2})}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.8

Factor

$- 1$ out of

$- 4 x^{2}$ .

$y' = \frac{x (- (4 x^{2}) + 25 - 4 y^{2})}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.9

Rewrite

$25$ as

$- 1 (- 25)$ .

$y' = \frac{x (- (4 x^{2}) - 1 (- 25) - 4 y^{2})}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.10

Factor

$- 1$ out of

$- (4 x^{2}) - 1 (- 25)$ .

$y' = \frac{x (- (4 x^{2} - 25) - 4 y^{2})}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.11

Factor

$- 1$ out of

$- 4 y^{2}$ .

$y' = \frac{x (- (4 x^{2} - 25) - (4 y^{2}))}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.12

Factor

$- 1$ out of

$- (4 x^{2} - 25) - (4 y^{2})$ .

$y' = \frac{x (- (4 x^{2} - 25 + 4 y^{2}))}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.13

Simplify the expression.

Tap for more steps...

Step 1.5.5.3.13.1

Rewrite

$- (4 x^{2} - 25 + 4 y^{2})$ as

$- 1 (4 x^{2} - 25 + 4 y^{2})$ .

$y' = \frac{x (- 1 (4 x^{2} - 25 + 4 y^{2}))}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.5.5.3.13.2

Move the negative in front of the fraction.

$y' = - \frac{x (4 x^{2} - 25 + 4 y^{2})}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.6

Replace

$y'$ with

$\frac{d y}{d x}$ .

$\frac{d y}{d x} = - \frac{x (4 x^{2} - 25 + 4 y^{2})}{y (4 x^{2} + 4 y^{2} + 25)}$

Step 1.7

Evaluate at

$x = 3$ and

$y = 1$ .

Tap for more steps...

Step 1.7.1

Replace the variable

$x$ with

$3$ in the expression.

$- \frac{(3) (4 {(3)}^{2} - 25 + 4 y^{2})}{y (4 {(3)}^{2} + 4 y^{2} + 25)}$

Step 1.7.2

Replace the variable

$y$ with

$1$ in the expression.

$- \frac{(3) (4 {(3)}^{2} - 25 + 4 {(1)}^{2})}{(1) (4 {(3)}^{2} + 4 {(1)}^{2} + 25)}$

Step 1.7.3

Simplify the numerator.

Tap for more steps...

Step 1.7.3.1

Raise

$3$ to the power of

$2$ .

$- \frac{3 (4 \cdot 9 - 25 + 4 \cdot 1^{2})}{1 (4 \cdot 3^{2} + 4 \cdot 1^{2} + 25)}$

Step 1.7.3.2

Multiply

$4$ by

$9$ .

$- \frac{3 (36 - 25 + 4 \cdot 1^{2})}{1 (4 \cdot 3^{2} + 4 \cdot 1^{2} + 25)}$

Step 1.7.3.3

One to any power is one.

$- \frac{3 (36 - 25 + 4 \cdot 1)}{1 (4 \cdot 3^{2} + 4 \cdot 1^{2} + 25)}$

Step 1.7.3.4

Multiply

$4$ by

$1$ .

$- \frac{3 (36 - 25 + 4)}{1 (4 \cdot 3^{2} + 4 \cdot 1^{2} + 25)}$

Step 1.7.3.5

Subtract

$25$ from

$36$ .

$- \frac{3 (11 + 4)}{1 (4 \cdot 3^{2} + 4 \cdot 1^{2} + 25)}$

Step 1.7.3.6

Add

$11$ and

$4$ .

$- \frac{3 \cdot 15}{1 (4 \cdot 3^{2} + 4 \cdot 1^{2} + 25)}$

Step 1.7.4

Multiply.

Tap for more steps...

Step 1.7.4.1

Multiply

$4 \cdot 3^{2} + 4 \cdot 1^{2} + 25$ by

$1$ .

$- \frac{3 \cdot 15}{4 \cdot 3^{2} + 4 \cdot 1^{2} + 25}$

Step 1.7.4.2

Multiply

$3$ by

$15$ .

$- \frac{45}{4 \cdot 3^{2} + 4 \cdot 1^{2} + 25}$

Step 1.7.5

Simplify the denominator.

Tap for more steps...

Step 1.7.5.1

Raise

$3$ to the power of

$2$ .

$- \frac{45}{4 \cdot 9 + 4 \cdot 1^{2} + 25}$

Step 1.7.5.2

Multiply

$4$ by

$9$ .

$- \frac{45}{36 + 4 \cdot 1^{2} + 25}$

Step 1.7.5.3

One to any power is one.

$- \frac{45}{36 + 4 \cdot 1 + 25}$

Step 1.7.5.4

Multiply

$4$ by

$1$ .

$- \frac{45}{36 + 4 + 25}$

Step 1.7.5.5

Add

$36$ and

$4$ .

$- \frac{45}{40 + 25}$

Step 1.7.5.6

Add

$40$ and

$25$ .

$- \frac{45}{65}$

Step 1.7.6

Cancel the common factor of

$45$ and

$65$ .

Tap for more steps...

Step 1.7.6.1

Factor

$5$ out of

$45$ .

$- \frac{5 (9)}{65}$

Step 1.7.6.2

Cancel the common factors.

Tap for more steps...

Step 1.7.6.2.1

Factor

$5$ out of

$65$ .

$- \frac{5 \cdot 9}{5 \cdot 13}$

Step 1.7.6.2.2

Cancel the common factor.

$- \frac{5 \cdot 9}{5 \cdot 13}$

Step 1.7.6.2.3

Rewrite the expression.

$- \frac{9}{13}$

Step 2

Plug the slope and point values into the point-slope formula and solve for

$y$ .

Tap for more steps...

Step 2.1

Use the slope

$- \frac{9}{13}$ and a given point

$(3, 1)$ to substitute for

$x_{1}$ and

$y_{1}$ in the point-slope form

$y - y_{1} = m (x - x_{1})$ , which is derived from the slope equation

$m = \frac{y_{2} - y_{1}}{x_{2} - x_{1}}$ .

$y - (1) = - \frac{9}{13} \cdot (x - (3))$

Step 2.2

Simplify the equation and keep it in point-slope form.

$y - 1 = - \frac{9}{13} \cdot (x - 3)$

Step 2.3

Solve for

$y$ .

Tap for more steps...

Step 2.3.1

Simplify

$- \frac{9}{13} \cdot (x - 3)$ .

Tap for more steps...

Step 2.3.1.1

Rewrite.

$y - 1 = 0 + 0 - \frac{9}{13} \cdot (x - 3)$

Step 2.3.1.2

Simplify by adding zeros.

$y - 1 = - \frac{9}{13} \cdot (x - 3)$

Step 2.3.1.3

Apply the distributive property.

$y - 1 = - \frac{9}{13} x - \frac{9}{13} \cdot - 3$

Step 2.3.1.4

Combine

$x$ and

$\frac{9}{13}$ .

$y - 1 = - \frac{x \cdot 9}{13} - \frac{9}{13} \cdot - 3$

Step 2.3.1.5

Multiply

$- \frac{9}{13} \cdot - 3$ .

Tap for more steps...

Step 2.3.1.5.1

Multiply

$- 3$ by

$- 1$ .

$y - 1 = - \frac{x \cdot 9}{13} + 3 (\frac{9}{13})$

Step 2.3.1.5.2

Combine

$3$ and

$\frac{9}{13}$ .

$y - 1 = - \frac{x \cdot 9}{13} + \frac{3 \cdot 9}{13}$

Step 2.3.1.5.3

Multiply

$3$ by

$9$ .

$y - 1 = - \frac{x \cdot 9}{13} + \frac{27}{13}$

Step 2.3.1.6

Move

$9$ to the left of

$x$ .

$y - 1 = - \frac{9 x}{13} + \frac{27}{13}$

Step 2.3.2

Move all terms not containing

$y$ to the right side of the equation.

Tap for more steps...

Step 2.3.2.1

Add

$1$ to both sides of the equation.

$y = - \frac{9 x}{13} + \frac{27}{13} + 1$

Step 2.3.2.2

Write

$1$ as a fraction with a common denominator.

$y = - \frac{9 x}{13} + \frac{27}{13} + \frac{13}{13}$

Step 2.3.2.3

Combine the numerators over the common denominator.

$y = - \frac{9 x}{13} + \frac{27 + 13}{13}$

Step 2.3.2.4

Add

$27$ and

$13$ .

$y = - \frac{9 x}{13} + \frac{40}{13}$

Step 2.3.3

Write in

$y = m x + b$ form.

Tap for more steps...

Step 2.3.3.1

Reorder terms.

$y = - (\frac{9}{13} x) + \frac{40}{13}$

Step 2.3.3.2

Remove parentheses.

$y = - \frac{9}{13} x + \frac{40}{13}$

Step 3