Calculus Examples

$y = 4 \arcsin (\frac{x}{2}) - x \sqrt{4 - x^{2}}$

Step 1

By the Sum Rule, the derivative of $4 \arcsin (\frac{x}{2}) - x \sqrt{4 - x^{2}}$ with respect to $x$ is $\frac{d}{d x} [4 \arcsin (\frac{x}{2})] + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$ .

$\frac{d}{d x} [4 \arcsin (\frac{x}{2})] + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2

Evaluate $\frac{d}{d x} [4 \arcsin (\frac{x}{2})]$ .

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Step 2.1

Since $4$ is constant with respect to $x$ , the derivative of $4 \arcsin (\frac{x}{2})$ with respect to $x$ is $4 \frac{d}{d x} [\arcsin (\frac{x}{2})]$ .

$4 \frac{d}{d x} [\arcsin (\frac{x}{2})] + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.2

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

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Step 2.2.1

To apply the Chain Rule, set $u_{1}$ as $\frac{x}{2}$ .

$4 (\frac{d}{d u_{1}} [\arcsin (u_{1})] \frac{d}{d x} [\frac{x}{2}]) + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.2.2

The derivative of $\arcsin (u_{1})$ with respect to $u_{1}$ is $\frac{1}{\sqrt{1 - {u_{1}}^{2}}}$ .

$4 (\frac{1}{\sqrt{1 - {u_{1}}^{2}}} \frac{d}{d x} [\frac{x}{2}]) + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.2.3

Replace all occurrences of $u_{1}$ with $\frac{x}{2}$ .

$4 (\frac{1}{\sqrt{1 - {(\frac{x}{2})}^{2}}} \frac{d}{d x} [\frac{x}{2}]) + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.3

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

$4 (\frac{1}{\sqrt{1 - {(\frac{x}{2})}^{2}}} (\frac{1}{2} \frac{d}{d x} [x])) + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.4

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

$4 (\frac{1}{\sqrt{1 - {(\frac{x}{2})}^{2}}} (\frac{1}{2} \cdot 1)) + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.5

Multiply $\frac{1}{2}$ by $1$ .

$4 (\frac{1}{\sqrt{1 - {(\frac{x}{2})}^{2}}} \cdot \frac{1}{2}) + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.6

Multiply $\frac{1}{\sqrt{1 - {(\frac{x}{2})}^{2}}}$ by $\frac{1}{2}$ .

$4 \frac{1}{\sqrt{1 - {(\frac{x}{2})}^{2}} \cdot 2} + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.7

Move $2$ to the left of $\sqrt{1 - {(\frac{x}{2})}^{2}}$ .

$4 \frac{1}{2 \cdot \sqrt{1 - {(\frac{x}{2})}^{2}}} + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.8

Combine $4$ and $\frac{1}{2 \sqrt{1 - {(\frac{x}{2})}^{2}}}$ .

$\frac{4}{2 \sqrt{1 - {(\frac{x}{2})}^{2}}} + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.9

Cancel the common factor of $4$ and $2$ .

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Step 2.9.1

Factor $2$ out of $4$ .

$\frac{2 \cdot 2}{2 \sqrt{1 - {(\frac{x}{2})}^{2}}} + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.9.2

Cancel the common factors.

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Step 2.9.2.1

Factor $2$ out of $2 \sqrt{1 - {(\frac{x}{2})}^{2}}$ .

$\frac{2 \cdot 2}{2 (\sqrt{1 - {(\frac{x}{2})}^{2}})} + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.9.2.2

Cancel the common factor.

$\frac{2 \cdot 2}{2 \sqrt{1 - {(\frac{x}{2})}^{2}}} + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 2.9.2.3

Rewrite the expression.

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} + \frac{d}{d x} [- x \sqrt{4 - x^{2}}]$

Step 3

Evaluate $\frac{d}{d x} [- x \sqrt{4 - x^{2}}]$ .

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Step 3.1

Use $\sqrt[n]{a^{x}} = a^{\frac{x}{n}}$ to rewrite $\sqrt{4 - x^{2}}$ as ${(4 - x^{2})}^{\frac{1}{2}}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} + \frac{d}{d x} [- x {(4 - x^{2})}^{\frac{1}{2}}]$

Step 3.2

Since $- 1$ is constant with respect to $x$ , the derivative of $- x {(4 - x^{2})}^{\frac{1}{2}}$ with respect to $x$ is $- \frac{d}{d x} [x {(4 - x^{2})}^{\frac{1}{2}}]$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - \frac{d}{d x} [x {(4 - x^{2})}^{\frac{1}{2}}]$

Step 3.3

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 $g (x) = {(4 - x^{2})}^{\frac{1}{2}}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x \frac{d}{d x} [{(4 - x^{2})}^{\frac{1}{2}}] + {(4 - x^{2})}^{\frac{1}{2}} \frac{d}{d x} [x])$

Step 3.4

Differentiate using the chain rule, which states that $\frac{d}{d x} [f (g (x))]$ is $f' (g (x)) g' (x)$ where $f (x) = x^{\frac{1}{2}}$ and $g (x) = 4 - x^{2}$ .

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Step 3.4.1

To apply the Chain Rule, set $u_{2}$ as $4 - x^{2}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{d}{d u_{2}} [{u_{2}}^{\frac{1}{2}}] \frac{d}{d x} [4 - x^{2}]) + {(4 - x^{2})}^{\frac{1}{2}} \frac{d}{d x} [x])$

Step 3.4.2

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

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {u_{2}}^{\frac{1}{2} - 1} \frac{d}{d x} [4 - x^{2}]) + {(4 - x^{2})}^{\frac{1}{2}} \frac{d}{d x} [x])$

Step 3.4.3

Replace all occurrences of $u_{2}$ with $4 - x^{2}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{\frac{1}{2} - 1} \frac{d}{d x} [4 - x^{2}]) + {(4 - x^{2})}^{\frac{1}{2}} \frac{d}{d x} [x])$

Step 3.5

By the Sum Rule, the derivative of $4 - x^{2}$ with respect to $x$ is $\frac{d}{d x} [4] + \frac{d}{d x} [- x^{2}]$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{\frac{1}{2} - 1} (\frac{d}{d x} [4] + \frac{d}{d x} [- x^{2}])) + {(4 - x^{2})}^{\frac{1}{2}} \frac{d}{d x} [x])$

Step 3.6

Since $4$ is constant with respect to $x$ , the derivative of $4$ with respect to $x$ is $0$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{\frac{1}{2} - 1} (0 + \frac{d}{d x} [- x^{2}])) + {(4 - x^{2})}^{\frac{1}{2}} \frac{d}{d x} [x])$

Step 3.7

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

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{\frac{1}{2} - 1} (0 - \frac{d}{d x} [x^{2}])) + {(4 - x^{2})}^{\frac{1}{2}} \frac{d}{d x} [x])$

Step 3.8

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

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{\frac{1}{2} - 1} (0 - (2 x))) + {(4 - x^{2})}^{\frac{1}{2}} \frac{d}{d x} [x])$

Step 3.9

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

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{\frac{1}{2} - 1} (0 - (2 x))) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.10

To write $- 1$ as a fraction with a common denominator, multiply by $\frac{2}{2}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{\frac{1}{2} - 1 \cdot \frac{2}{2}} (0 - (2 x))) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.11

Combine $- 1$ and $\frac{2}{2}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{\frac{1}{2} + \frac{- 1 \cdot 2}{2}} (0 - (2 x))) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.12

Combine the numerators over the common denominator.

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{\frac{1 - 1 \cdot 2}{2}} (0 - (2 x))) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.13

Simplify the numerator.

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Step 3.13.1

Multiply $- 1$ by $2$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{\frac{1 - 2}{2}} (0 - (2 x))) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.13.2

Subtract $2$ from $1$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{\frac{- 1}{2}} (0 - (2 x))) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.14

Move the negative in front of the fraction.

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{- \frac{1}{2}} (0 - (2 x))) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.15

Multiply $2$ by $- 1$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{- \frac{1}{2}} (0 - 2 x)) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.16

Subtract $2 x$ from $0$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{1}{2} {(4 - x^{2})}^{- \frac{1}{2}} (- 2 x)) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.17

Combine $\frac{1}{2}$ and ${(4 - x^{2})}^{- \frac{1}{2}}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{{(4 - x^{2})}^{- \frac{1}{2}}}{2} (- 2 x)) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.18

Combine $- 2$ and $\frac{{(4 - x^{2})}^{- \frac{1}{2}}}{2}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (\frac{- 2 {(4 - x^{2})}^{- \frac{1}{2}}}{2} x) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.19

Combine $\frac{- 2 {(4 - x^{2})}^{- \frac{1}{2}}}{2}$ and $x$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x \frac{- 2 {(4 - x^{2})}^{- \frac{1}{2}} x}{2} + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.20

Move ${(4 - x^{2})}^{- \frac{1}{2}}$ to the denominator using the negative exponent rule $b^{- n} = \frac{1}{b^{n}}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x \frac{- 2 x}{2 {(4 - x^{2})}^{\frac{1}{2}}} + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.21

Factor $2$ out of $- 2 x$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x \frac{2 (- x)}{2 {(4 - x^{2})}^{\frac{1}{2}}} + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.22

Cancel the common factors.

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Step 3.22.1

Factor $2$ out of $2 {(4 - x^{2})}^{\frac{1}{2}}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x \frac{2 (- x)}{2 ({(4 - x^{2})}^{\frac{1}{2}})} + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.22.2

Cancel the common factor.

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x \frac{2 (- x)}{2 {(4 - x^{2})}^{\frac{1}{2}}} + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.22.3

Rewrite the expression.

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x \frac{- x}{{(4 - x^{2})}^{\frac{1}{2}}} + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.23

Move the negative in front of the fraction.

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (x (- \frac{x}{{(4 - x^{2})}^{\frac{1}{2}}}) + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.24

Combine $x$ and $\frac{x}{{(4 - x^{2})}^{\frac{1}{2}}}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (- \frac{x \cdot x}{{(4 - x^{2})}^{\frac{1}{2}}} + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.25

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

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (- \frac{x^{1} x}{{(4 - x^{2})}^{\frac{1}{2}}} + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.26

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

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (- \frac{x^{1} x^{1}}{{(4 - x^{2})}^{\frac{1}{2}}} + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.27

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

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (- \frac{x^{1 + 1}}{{(4 - x^{2})}^{\frac{1}{2}}} + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.28

Add $1$ and $1$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (- \frac{x^{2}}{{(4 - x^{2})}^{\frac{1}{2}}} + {(4 - x^{2})}^{\frac{1}{2}} \cdot 1)$

Step 3.29

Multiply ${(4 - x^{2})}^{\frac{1}{2}}$ by $1$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (- \frac{x^{2}}{{(4 - x^{2})}^{\frac{1}{2}}} + {(4 - x^{2})}^{\frac{1}{2}})$

Step 3.30

To write ${(4 - x^{2})}^{\frac{1}{2}}$ as a fraction with a common denominator, multiply by $\frac{{(4 - x^{2})}^{\frac{1}{2}}}{{(4 - x^{2})}^{\frac{1}{2}}}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - (- \frac{x^{2}}{{(4 - x^{2})}^{\frac{1}{2}}} + \frac{{(4 - x^{2})}^{\frac{1}{2}} {(4 - x^{2})}^{\frac{1}{2}}}{{(4 - x^{2})}^{\frac{1}{2}}})$

Step 3.31

Combine the numerators over the common denominator.

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - \frac{- x^{2} + {(4 - x^{2})}^{\frac{1}{2}} {(4 - x^{2})}^{\frac{1}{2}}}{{(4 - x^{2})}^{\frac{1}{2}}}$

Step 3.32

Multiply ${(4 - x^{2})}^{\frac{1}{2}}$ by ${(4 - x^{2})}^{\frac{1}{2}}$ by adding the exponents.

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Step 3.32.1

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

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - \frac{- x^{2} + {(4 - x^{2})}^{\frac{1}{2} + \frac{1}{2}}}{{(4 - x^{2})}^{\frac{1}{2}}}$

Step 3.32.2

Combine the numerators over the common denominator.

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - \frac{- x^{2} + {(4 - x^{2})}^{\frac{1 + 1}{2}}}{{(4 - x^{2})}^{\frac{1}{2}}}$

Step 3.32.3

Add $1$ and $1$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - \frac{- x^{2} + {(4 - x^{2})}^{\frac{2}{2}}}{{(4 - x^{2})}^{\frac{1}{2}}}$

Step 3.32.4

Divide $2$ by $2$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - \frac{- x^{2} + {(4 - x^{2})}^{1}}{{(4 - x^{2})}^{\frac{1}{2}}}$

Step 3.33

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

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - \frac{- x^{2} + 4 - x^{2}}{{(4 - x^{2})}^{\frac{1}{2}}}$

Step 3.34

Subtract $x^{2}$ from $- x^{2}$ .

$\frac{2}{\sqrt{1 - {(\frac{x}{2})}^{2}}} - \frac{- 2 x^{2} + 4}{{(4 - x^{2})}^{\frac{1}{2}}}$

Step 4

Simplify.

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Step 4.1

Apply the product rule to $\frac{x}{2}$ .

$\frac{2}{\sqrt{1 - \frac{x^{2}}{2^{2}}}} - \frac{- 2 x^{2} + 4}{{(4 - x^{2})}^{\frac{1}{2}}}$

Step 4.2

Combine terms.

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Step 4.2.1

Raise $2$ to the power of $2$ .

$\frac{2}{\sqrt{1 - \frac{x^{2}}{4}}} - \frac{- 2 x^{2} + 4}{{(4 - x^{2})}^{\frac{1}{2}}}$

Step 4.2.2

To write $\frac{2}{\sqrt{1 - \frac{x^{2}}{4}}}$ as a fraction with a common denominator, multiply by $\frac{{(4 - x^{2})}^{\frac{1}{2}}}{{(4 - x^{2})}^{\frac{1}{2}}}$ .

$\frac{2}{\sqrt{1 - \frac{x^{2}}{4}}} \cdot \frac{{(4 - x^{2})}^{\frac{1}{2}}}{{(4 - x^{2})}^{\frac{1}{2}}} - \frac{- 2 x^{2} + 4}{{(4 - x^{2})}^{\frac{1}{2}}}$

Step 4.2.3

To write $- \frac{- 2 x^{2} + 4}{{(4 - x^{2})}^{\frac{1}{2}}}$ as a fraction with a common denominator, multiply by $\frac{\sqrt{1 - \frac{x^{2}}{4}}}{\sqrt{1 - \frac{x^{2}}{4}}}$ .

$\frac{2}{\sqrt{1 - \frac{x^{2}}{4}}} \cdot \frac{{(4 - x^{2})}^{\frac{1}{2}}}{{(4 - x^{2})}^{\frac{1}{2}}} - \frac{- 2 x^{2} + 4}{{(4 - x^{2})}^{\frac{1}{2}}} \cdot \frac{\sqrt{1 - \frac{x^{2}}{4}}}{\sqrt{1 - \frac{x^{2}}{4}}}$

Step 4.2.4

Write each expression with a common denominator of $\sqrt{1 - \frac{x^{2}}{4}} {(4 - x^{2})}^{\frac{1}{2}}$ , by multiplying each by an appropriate factor of $1$ .

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Step 4.2.4.1

Multiply $\frac{2}{\sqrt{1 - \frac{x^{2}}{4}}}$ by $\frac{{(4 - x^{2})}^{\frac{1}{2}}}{{(4 - x^{2})}^{\frac{1}{2}}}$ .

$\frac{2 {(4 - x^{2})}^{\frac{1}{2}}}{\sqrt{1 - \frac{x^{2}}{4}} {(4 - x^{2})}^{\frac{1}{2}}} - \frac{- 2 x^{2} + 4}{{(4 - x^{2})}^{\frac{1}{2}}} \cdot \frac{\sqrt{1 - \frac{x^{2}}{4}}}{\sqrt{1 - \frac{x^{2}}{4}}}$

Step 4.2.4.2

Multiply $\frac{- 2 x^{2} + 4}{{(4 - x^{2})}^{\frac{1}{2}}}$ by $\frac{\sqrt{1 - \frac{x^{2}}{4}}}{\sqrt{1 - \frac{x^{2}}{4}}}$ .

$\frac{2 {(4 - x^{2})}^{\frac{1}{2}}}{\sqrt{1 - \frac{x^{2}}{4}} {(4 - x^{2})}^{\frac{1}{2}}} - \frac{(- 2 x^{2} + 4) \sqrt{1 - \frac{x^{2}}{4}}}{{(4 - x^{2})}^{\frac{1}{2}} \sqrt{1 - \frac{x^{2}}{4}}}$

Step 4.2.4.3

Reorder the factors of $\sqrt{1 - \frac{x^{2}}{4}} {(4 - x^{2})}^{\frac{1}{2}}$ .

$\frac{2 {(4 - x^{2})}^{\frac{1}{2}}}{{(4 - x^{2})}^{\frac{1}{2}} \sqrt{1 - \frac{x^{2}}{4}}} - \frac{(- 2 x^{2} + 4) \sqrt{1 - \frac{x^{2}}{4}}}{{(4 - x^{2})}^{\frac{1}{2}} \sqrt{1 - \frac{x^{2}}{4}}}$

Step 4.2.5

Combine the numerators over the common denominator.

$\frac{2 {(4 - x^{2})}^{\frac{1}{2}} - (- 2 x^{2} + 4) \sqrt{1 - \frac{x^{2}}{4}}}{{(4 - x^{2})}^{\frac{1}{2}} \sqrt{1 - \frac{x^{2}}{4}}}$

Step 4.3

Reorder terms.

$\frac{- \sqrt{1 - \frac{x^{2}}{4}} (- 2 x^{2} + 4) + 2 {(4 - x^{2})}^{\frac{1}{2}}}{{(4 - x^{2})}^{\frac{1}{2}} \sqrt{1 - \frac{x^{2}}{4}}}$