Question
Integrate the function: $\frac{{2\cos x - 3\sin x}}{{6\cos x + 4\sin x}}$

Answer

Let $I = \int {\frac{{2\cos x - 3\sin x}}{{6\cos x + 4\sin x}}dx} $

$ = \int {\frac{{2\cos x - 3\sin x}}{{2\left( {2\sin x + 3\cos x} \right)}}dx} $

$= \frac{1}{2}\int {\frac{{2\cos x - 3\sin x}}{{2\sin x + 3\cos x}}dx} $…(i)

Putting 2 sin x + 3 cos x = t

$ \Rightarrow 2\cos x - 3\sin x = \frac{{dt}}{{dx}}$

$ \Rightarrow $ (2 cos x - 3 sin x)dx = dt

$\therefore$ From eq. (i), $I = \frac{1}{2}\int {\frac{{dt}}{t} = \frac{1}{2}\log \left| t \right| + c} $

$= \frac{1}{2}\log \left| {2\sin x + 3\cos x} \right| + c$

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

The length $x$ of a rectangle is decreasing at the rate of 5 cm/minute. and the width is increasing at the rate of $\text{4 cm/minute}.$ When $x = 8\ cm$ and $y = 6\ cm$, find the rates of change of,
  1. The perimeter and,
  2. The area of the rectangle.
Evaluate the following integrals:$\int\text{e}^{\sqrt{\text{x}}}\text{dx}$
Find the value of $\cot \frac{1}{2} \bigg[ \cos^{-1} \frac{\text{2x}}{\text{1 + x}^{2}} + \sin^{-1} \frac{1- \text{y}^{2}}{\text{1+ y}^{2}}\bigg], \text{|x|} < 1, \text{y} > 0 \text{ and xy} < 1.$
The radius of an air bubble is increasing at the rate of 0.5cm/ sec. At what rate is the volume of the bubble increasing when the radius is 1cm?
For each of the differential equation given in find the general solution: $\text{x}\log\text{x}\frac{\text{dy}}{\text{dx}}+\text{y}=\frac{2}{\text{x}}\log\text{x}$
If $\text{y}=\frac{\log\text{x}}{\text{x}},$ show that $\frac{\text{d}^2\text{y}}{\text{dx}^2}=\frac{2\log\text{x}-3}{\text{x}^3}.$
By using the properties of definite integrals, evaluate the integral $\int\limits_0^2 {x\sqrt {2 - x} dx} $
Evaluate the following integrals:
$\int\limits^{\frac{\pi}{2}}_0\text{e}^{\text{x}}(\sin\text{x}-\cos\text{x})\text{dx}$
If $\vec{\text{a}}=2\hat{\text{i}}-\hat{\text{j}}+\hat{\text{k}},\vec{\text{b}}=\hat{\text{i}}+\hat{\text{j}}-2\hat{\text{k}}$ and $\vec{\text{c}}=\hat{\text{i}}+3\hat{\text{j}}-\hat{\text{k}}.$ find $\lambda$ such that $\vec{\text{a}}$ is perpendicular to $\lambda\vec{\text{b}}+\vec{\text{c}}.$
Evaluate the following definite integrals:
$\int_{0}^\limits{1}\text{x}(1-\text{x})^5\text{ dx}$