Calculus Examples

$y = 7^{2 x} \log (7 x^{3} - 4 x + 5)$

Step 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 $f (x) = 7^{2 x}$ and $g (x) = \log (7 x^{3} - 4 x + 5)$ .

$7^{2 x} \frac{d}{d x} [\log (7 x^{3} - 4 x + 5)] + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 2

Differentiate using the chain rule, which states that $\frac{d}{d x} [f (g (x))]$ is $f' (g (x)) g' (x)$ where $f (x) = \log (x)$ and $g (x) = 7 x^{3} - 4 x + 5$ .

Tap for more steps...

Step 2.1

To apply the Chain Rule, set $u_{1}$ as $7 x^{3} - 4 x + 5$ .

$7^{2 x} (\frac{d}{d u_{1}} [\log (u_{1})] \frac{d}{d x} [7 x^{3} - 4 x + 5]) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 2.2

The derivative of $\log (u_{1})$ with respect to $u_{1}$ is $\frac{1}{u_{1} \ln (10)}$ .

$7^{2 x} (\frac{1}{u_{1} \ln (10)} \frac{d}{d x} [7 x^{3} - 4 x + 5]) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 2.3

Replace all occurrences of $u_{1}$ with $7 x^{3} - 4 x + 5$ .

$7^{2 x} (\frac{1}{(7 x^{3} - 4 x + 5) \ln (10)} \frac{d}{d x} [7 x^{3} - 4 x + 5]) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 3

Differentiate.

Tap for more steps...

Step 3.1

Combine $\frac{1}{(7 x^{3} - 4 x + 5) \ln (10)}$ and $7^{2 x}$ .

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} \frac{d}{d x} [7 x^{3} - 4 x + 5] + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 3.2

By the Sum Rule, the derivative of $7 x^{3} - 4 x + 5$ with respect to $x$ is $\frac{d}{d x} [7 x^{3}] + \frac{d}{d x} [- 4 x] + \frac{d}{d x} [5]$ .

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (\frac{d}{d x} [7 x^{3}] + \frac{d}{d x} [- 4 x] + \frac{d}{d x} [5]) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 3.3

Since $7$ is constant with respect to $x$ , the derivative of $7 x^{3}$ with respect to $x$ is $7 \frac{d}{d x} [x^{3}]$ .

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (7 \frac{d}{d x} [x^{3}] + \frac{d}{d x} [- 4 x] + \frac{d}{d x} [5]) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 3.4

Differentiate using the Power Rule which states that $\frac{d}{d x} [x^{n}]$ is $n x^{n - 1}$ where $n = 3$ .

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (7 (3 x^{2}) + \frac{d}{d x} [- 4 x] + \frac{d}{d x} [5]) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 3.5

Multiply $3$ by $7$ .

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} + \frac{d}{d x} [- 4 x] + \frac{d}{d x} [5]) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 3.6

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

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4 \frac{d}{d x} [x] + \frac{d}{d x} [5]) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 3.7

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

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4 \cdot 1 + \frac{d}{d x} [5]) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 3.8

Multiply $- 4$ by $1$ .

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4 + \frac{d}{d x} [5]) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 3.9

Since $5$ is constant with respect to $x$ , the derivative of $5$ with respect to $x$ is $0$ .

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4 + 0) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 3.10

Add $21 x^{2} - 4$ and $0$ .

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4) + \log (7 x^{3} - 4 x + 5) \frac{d}{d x} [7^{2 x}]$

Step 4

Differentiate using the chain rule, which states that $\frac{d}{d x} [f (g (x))]$ is $f' (g (x)) g' (x)$ where $f (x) = 7^{x}$ and $g (x) = 2 x$ .

Tap for more steps...

Step 4.1

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

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4) + \log (7 x^{3} - 4 x + 5) (\frac{d}{d u_{2}} [7^{u_{2}}] \frac{d}{d x} [2 x])$

Step 4.2

Differentiate using the Exponential Rule which states that $\frac{d}{d u_{2}} [a^{u_{2}}]$ is $a^{u_{2}} \ln (a)$ where $a$ = $7$ .

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4) + \log (7 x^{3} - 4 x + 5) (7^{u_{2}} \ln (7) \frac{d}{d x} [2 x])$

Step 4.3

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

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4) + \log (7 x^{3} - 4 x + 5) (7^{2 x} \ln (7) \frac{d}{d x} [2 x])$

Step 5

Differentiate.

Tap for more steps...

Step 5.1

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

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4) + \log (7 x^{3} - 4 x + 5) (7^{2 x} \ln (7) (2 \frac{d}{d x} [x]))$

Step 5.2

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

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4) + \log (7 x^{3} - 4 x + 5) (7^{2 x} \ln (7) (2 \cdot 1))$

Step 5.3

Simplify the expression.

Tap for more steps...

Step 5.3.1

Multiply $2$ by $1$ .

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4) + \log (7 x^{3} - 4 x + 5) (7^{2 x} \ln (7) \cdot 2)$

Step 5.3.2

Move $2$ to the left of $7^{2 x} \ln (7)$ .

$\frac{7^{2 x}}{(7 x^{3} - 4 x + 5) \ln (10)} (21 x^{2} - 4) + \log (7 x^{3} - 4 x + 5) (2 \cdot (7^{2 x} \ln (7)))$

Step 6

Simplify.

Tap for more steps...

Step 6.1

Apply the distributive property.

$\frac{7^{2 x}}{7 x^{3} \ln (10) - 4 x \ln (10) + 5 \ln (10)} (21 x^{2} - 4) + \log (7 x^{3} - 4 x + 5) (2 \cdot 7^{2 x} \ln (7))$

Step 6.2

Reorder terms.

$(21 x^{2} - 4) \frac{7^{2 x}}{7 x^{3} \ln (10) - 4 x \ln (10) + 5 \ln (10)} + 2 \cdot 7^{2 x} \ln (7) \log (7 x^{3} - 4 x + 5)$