Calculus Examples

$y = t \ln^{2} (7 t)$

Step 1

Differentiate using the Product Rule which states that $\frac{d}{d t} [f (t) g (t)]$ is $f (t) \frac{d}{d t} [g (t)] + g (t) \frac{d}{d t} [f (t)]$ where $f (t) = t$ and $g (t) = \ln^{2} (7 t)$ .

$t \frac{d}{d t} [\ln^{2} (7 t)] + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 2

Differentiate using the chain rule, which states that $\frac{d}{d t} [f (g (t))]$ is $f' (g (t)) g' (t)$ where $f (t) = t^{2}$ and $g (t) = \ln (7 t)$ .

Tap for more steps...

Step 2.1

To apply the Chain Rule, set $u_{1}$ as $\ln (7 t)$ .

$t (\frac{d}{d u_{1}} [{u_{1}}^{2}] \frac{d}{d t} [\ln (7 t)]) + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 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 $n = 2$ .

$t (2 u_{1} \frac{d}{d t} [\ln (7 t)]) + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 2.3

Replace all occurrences of $u_{1}$ with $\ln (7 t)$ .

$t (2 \ln (7 t) \frac{d}{d t} [\ln (7 t)]) + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 3

Differentiate using the chain rule, which states that $\frac{d}{d t} [f (g (t))]$ is $f' (g (t)) g' (t)$ where $f (t) = \ln (t)$ and $g (t) = 7 t$ .

Tap for more steps...

Step 3.1

To apply the Chain Rule, set $u_{2}$ as $7 t$ .

$t (2 \ln (7 t) (\frac{d}{d u_{2}} [\ln (u_{2})] \frac{d}{d t} [7 t])) + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 3.2

The derivative of $\ln (u_{2})$ with respect to $u_{2}$ is $\frac{1}{u_{2}}$ .

$t (2 \ln (7 t) (\frac{1}{u_{2}} \frac{d}{d t} [7 t])) + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 3.3

Replace all occurrences of $u_{2}$ with $7 t$ .

$t (2 \ln (7 t) (\frac{1}{7 t} \frac{d}{d t} [7 t])) + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4

Differentiate.

Tap for more steps...

Step 4.1

Combine $\frac{1}{7 t}$ and $2$ .

$t (\frac{2}{7 t} \ln (7 t) \frac{d}{d t} [7 t]) + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.2

Simplify terms.

Tap for more steps...

Step 4.2.1

Combine $\frac{2}{7 t}$ and $\ln (7 t)$ .

$t (\frac{2 \ln (7 t)}{7 t} \frac{d}{d t} [7 t]) + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.2.2

Combine $\frac{2 \ln (7 t)}{7 t}$ and $t$ .

$\frac{2 \ln (7 t) t}{7 t} \frac{d}{d t} [7 t] + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.2.3

Cancel the common factor of $t$ .

Tap for more steps...

Step 4.2.3.1

Cancel the common factor.

$\frac{2 \ln (7 t) t}{7 t} \frac{d}{d t} [7 t] + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.2.3.2

Rewrite the expression.

$\frac{2 \ln (7 t)}{7} \frac{d}{d t} [7 t] + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.3

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

$\frac{2 \ln (7 t)}{7} (7 \frac{d}{d t} [t]) + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.4

Simplify terms.

Tap for more steps...

Step 4.4.1

Combine $7$ and $\frac{2 \ln (7 t)}{7}$ .

$\frac{7 (2 \ln (7 t))}{7} \frac{d}{d t} [t] + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.4.2

Multiply $2$ by $7$ .

$\frac{14 \ln (7 t)}{7} \frac{d}{d t} [t] + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.4.3

Cancel the common factor of $14$ and $7$ .

Tap for more steps...

Step 4.4.3.1

Factor $7$ out of $14 \ln (7 t)$ .

$\frac{7 (2 \ln (7 t))}{7} \frac{d}{d t} [t] + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.4.3.2

Cancel the common factors.

Tap for more steps...

Step 4.4.3.2.1

Factor $7$ out of $7$ .

$\frac{7 (2 \ln (7 t))}{7 (1)} \frac{d}{d t} [t] + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.4.3.2.2

Cancel the common factor.

$\frac{7 (2 \ln (7 t))}{7 \cdot 1} \frac{d}{d t} [t] + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.4.3.2.3

Rewrite the expression.

$\frac{2 \ln (7 t)}{1} \frac{d}{d t} [t] + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.4.3.2.4

Divide $2 \ln (7 t)$ by $1$ .

$2 \ln (7 t) \frac{d}{d t} [t] + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.5

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

$2 \ln (7 t) \cdot 1 + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.6

Multiply $2$ by $1$ .

$2 \ln (7 t) + \ln^{2} (7 t) \frac{d}{d t} [t]$

Step 4.7

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

$2 \ln (7 t) + \ln^{2} (7 t) \cdot 1$

Step 4.8

Simplify the expression.

Tap for more steps...

Step 4.8.1

Multiply $\ln^{2} (7 t)$ by $1$ .

$2 \ln (7 t) + \ln^{2} (7 t)$

Step 4.8.2

Reorder terms.

$\ln^{2} (7 t) + 2 \ln (7 t)$