Calculus Examples

$y = 2 \sin (x) \cos (x)$

Step 1

Differentiate both sides of the equation.

$\frac{d}{d x} (y) = \frac{d}{d x} (2 \sin (x) \cos (x))$

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

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

$2 \frac{d}{d x} [\sin (x) \cos (x)]$

Step 3.2

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 $f (x) = \sin (x)$ and $g (x) = \cos (x)$ .

$2 (\sin (x) \frac{d}{d x} [\cos (x)] + \cos (x) \frac{d}{d x} [\sin (x)])$

Step 3.3

The derivative of $\cos (x)$ with respect to $x$ is $- \sin (x)$ .

$2 (\sin (x) (- \sin (x)) + \cos (x) \frac{d}{d x} [\sin (x)])$

Step 3.4

Raise $\sin (x)$ to the power of $1$ .

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

Step 3.5

Raise $\sin (x)$ to the power of $1$ .

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

Step 3.6

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

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

Step 3.7

Add $1$ and $1$ .

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

Step 3.8

The derivative of $\sin (x)$ with respect to $x$ is $\cos (x)$ .

$2 (- \sin^{2} (x) + \cos (x) \cos (x))$

Step 3.9

Raise $\cos (x)$ to the power of $1$ .

$2 (- \sin^{2} (x) + \cos^{1} (x) \cos (x))$

Step 3.10

Raise $\cos (x)$ to the power of $1$ .

$2 (- \sin^{2} (x) + \cos^{1} (x) \cos^{1} (x))$

Step 3.11

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

$2 (- \sin^{2} (x) + {\cos (x)}^{1 + 1})$

Step 3.12

Add $1$ and $1$ .

$2 (- \sin^{2} (x) + \cos^{2} (x))$

Step 3.13

Simplify.

Tap for more steps...

Step 3.13.1

Apply the distributive property.

$2 (- \sin^{2} (x)) + 2 \cos^{2} (x)$

Step 3.13.2

Multiply $- 1$ by $2$ .

$- 2 \sin^{2} (x) + 2 \cos^{2} (x)$

Step 4

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

$y' = - 2 \sin^{2} (x) + 2 \cos^{2} (x)$

Step 5

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

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