Calculus Examples

$y = x e^{- x^{2}}$

Step 1

Differentiate both sides of the equation.

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

Step 2

The derivative of $y$ with respect to $x$ is $y'$ .

$y'$

Step 3

Differentiate the right side of the equation.

Tap for more steps...

Step 3.1

Differentiate using the Product Rule which states that $\frac{d}{d x} [f (x) g (x)]$ is $f (x) \frac{d}{d x} [g (x)] + g (x) \frac{d}{d x} [f (x)]$ where $f (x) = x$ and $g (x) = e^{- x^{2}}$ .

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

Step 3.2

Differentiate using the chain rule, which states that $\frac{d}{d x} [f (g (x))]$ is $f' (g (x)) g' (x)$ where $f (x) = e^{x}$ and $g (x) = - x^{2}$ .

Tap for more steps...

Step 3.2.1

To apply the Chain Rule, set $u$ as $- x^{2}$ .

$x (\frac{d}{d u} [e^{u}] \frac{d}{d x} [- x^{2}]) + e^{- x^{2}} \frac{d}{d x} [x]$

Step 3.2.2

Differentiate using the Exponential Rule which states that $\frac{d}{d u} [a^{u}]$ is $a^{u} \ln (a)$ where $a$ = $e$ .

$x (e^{u} \frac{d}{d x} [- x^{2}]) + e^{- x^{2}} \frac{d}{d x} [x]$

Step 3.2.3

Replace all occurrences of $u$ with $- x^{2}$ .

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

Step 3.3

Differentiate.

Tap for more steps...

Step 3.3.1

Since $- 1$ is constant with respect to $x$ , the derivative of $- x^{2}$ with respect to $x$ is $- \frac{d}{d x} [x^{2}]$ .

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

Step 3.3.2

Differentiate using the Power Rule which states that $\frac{d}{d x} [x^{n}]$ is $n x^{n - 1}$ where $n = 2$ .

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

Step 3.3.3

Multiply $2$ by $- 1$ .

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

Step 3.4

Raise $x$ to the power of $1$ .

$x^{1} x (e^{- x^{2}} \cdot (- 2)) + e^{- x^{2}} \frac{d}{d x} [x]$

Step 3.5

Raise $x$ to the power of $1$ .

$x^{1} x^{1} (e^{- x^{2}} \cdot (- 2)) + e^{- x^{2}} \frac{d}{d x} [x]$

Step 3.6

Use the power rule $a^{m} a^{n} = a^{m + n}$ to combine exponents.

$x^{1 + 1} (e^{- x^{2}} \cdot (- 2)) + e^{- x^{2}} \frac{d}{d x} [x]$

Step 3.7

Simplify the expression.

Tap for more steps...

Step 3.7.1

Add $1$ and $1$ .

$x^{2} (e^{- x^{2}} \cdot (- 2)) + e^{- x^{2}} \frac{d}{d x} [x]$

Step 3.7.2

Move $- 2$ to the left of $e^{- x^{2}}$ .

$x^{2} (- 2 \cdot e^{- x^{2}}) + e^{- x^{2}} \frac{d}{d x} [x]$

Step 3.8

Differentiate using the Power Rule which states that $\frac{d}{d x} [x^{n}]$ is $n x^{n - 1}$ where $n = 1$ .

$x^{2} (- 2 e^{- x^{2}}) + e^{- x^{2}} \cdot 1$

Step 3.9

Multiply $e^{- x^{2}}$ by $1$ .

$x^{2} (- 2 e^{- x^{2}}) + e^{- x^{2}}$

Step 3.10

Simplify.

Tap for more steps...

Step 3.10.1

Reorder terms.

$- 2 e^{- x^{2}} x^{2} + e^{- x^{2}}$

Step 3.10.2

Reorder factors in $- 2 e^{- x^{2}} x^{2} + e^{- x^{2}}$ .

$- 2 x^{2} e^{- x^{2}} + e^{- x^{2}}$

Step 4

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

$y' = - 2 x^{2} e^{- x^{2}} + e^{- x^{2}}$

Step 5

Replace $y'$ with $\frac{d y}{d x}$ .

$\frac{d y}{d x} = - 2 x^{2} e^{- x^{2}} + e^{- x^{2}}$