Question
Differentiate the following function with respect to x:

$\text{x}^4(5\sin\text{x}-3\cos\text{x})$

Answer

Let $\text{u}=\text{x}^4;\text{v}=​5\sin\text{x}-3\cos\text{x}$

Then, $\text{u}'=\text{4x}^3;\text{v}'=5\cos\text{x}-3(-\sin\text{x})=5\cos\text{x}+3\sin\text{x}$

Using the product rule:

$\frac{\text{d}}{\text{dx}}(\text{uv})=\text{u}'\text{v}+\text{uv}'$

$\frac{\text{d}}{\text{dx}}(\text{x}^4(5\sin\text{x}-3\cos\text{x}))=\text{x}^4(5\cos\text{x}+3\sin\text{x})+\text{4x}^3(5\sin\text{x}-3\cos\text{x})$

$=\text{x}^3(\text{5x}\cos\text{x}+\text{3x}\sin\text{x}+20\sin\text{x}-12\cos\text{x})$

$=\text{x}^3((\text{3x}+20)\sin\text{x}+(\text{5x}-12)\cos\text{x})$

$=\text{3x}^4\sin\text{x}+20\text{x}^3\sin\text{x}+\text{5x}\cos\text{x}-12\cos\text{x}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Find the angle between the lines x = a and by + c = 0.
Evaluate:
$\lim\limits_{\text{x} \rightarrow0}\frac{\sqrt{2}-\sqrt{1+\cos\text{x}}}{\sin^{2}\text{x}}$
Find the equations of the circles touching y-axis at (0, 3) and making an intercept of 8 units on the x-axis.
Find the point to which the origin should be shifted after a translation of axes so that the following equations will have no first deree terms:
x2 + y2 - 5x + 2y - 5 = 0
The mean and standard deviation of 100 observations were calculated as 40 and 5.1, respectively by a student who took by mistake 50 instead of 40 for one observation. What are the correct mean and standard deviation?
Find $\sin\frac{\text{x}}{2},\cos\frac{\text{x}}{2}$ and $\tan\frac{\text{x}}{2}$ in each of the following :
$\tan\text{x}=-\frac{4}{3},$ x in quadrant II
The mean and variance of 7 observations are 8 and 16 respectively. If five of the observations are 2, 4, 10, 12, 14 find the remaining two observations.
Evaluate the following limit:
$\lim\limits_{\text{x}\rightarrow7}\frac{4-\sqrt{9+\text{x}}}{1-\sqrt{8-\text{x}}}$
Evaluate the following limit:
$\lim\limits_{\text{x}\rightarrow0}\frac{\sqrt{1+\text{x}+\text{x}^2}-\sqrt{\text{x}+1}}{2\text{x}^2}$
In a survey of 60 people, it was found that 25 people read newspaper H, 26 read newspaper T, 26 read newspaper I, 9 read both H and I, 11 read both H and T, 8 read both T and I, 3 read all three newspapers. Find:
The number of people who read at least one of the newspapers.