Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NDA 2016
Exam
NDA
Year
2016
Subject
Mathematics
Chapter
Indefinite Integration

NDA 2016 · Mathematics · Indefinite Integration

What is ∫ e^ x (x ^3 x- x)/( ^2 x) d x equal to?

What is ∫esin⁡xxcos⁡3x−sin⁡xcos⁡2xdx\int e^{\sin x} \frac{x \cos ^3 x-\sin x}{\cos ^2 x} d x equal to?

Options

  1. A(x+sec⁡x)esin⁡x+c(x+\sec x) e^{\sin x}+c
  2. B(x−sec⁡x)esin⁡x+c(x-\sec x) e^{\sin x}+c
  3. C(x+tan⁡x)esin⁡x+c(x+\tan x) e^{\sin x}+c
  4. D(x−tan⁡x)esin⁡x+c(x-\tan x) e^{\sin x}+c

Correct answer

B. (x−sec⁡x)esin⁡x+c(x-\sec x) e^{\sin x}+c

Step-by-step solution

Let us differentiate all the options one by one to get the expression in the question whose integral is to be found. Here xesin⁡xx e^{\sin x} is the common term in all the options. So, let us differentiate it first.  Let l=xesin⁡x⇒dldx=esin⁡x[xcos⁡x+1]⇒dldx=esin⁡xcos⁡2x[xcos⁡3x+cos⁡2x]\begin{aligned} & \text{ Let } l=x e^{\sin x} \\ & \Rightarrow \frac{d l}{d x}=e^{\sin x}[x \cos x+1] \\ & \Rightarrow \frac{d l}{d x}=\frac{e^{\sin x}}{\cos ^2 x}\left[x \cos ^3 x+\cos ^2 x\right] \end{aligned} Let m=sec⁡xesin⁡xm=\sec x e^{\sin x}⇒dmdx=sec⁡xesin⁡x⋅cos⁡x+esin⁡xsec⁡xtan⁡x⇒dmdx=esin⁡x[1+sin⁡xcos⁡2x]⇒dmdx=esin⁡xcos⁡2x[cos⁡2x+sin⁡x]\begin{aligned} & \Rightarrow \frac{d m}{d x}=\sec x e^{\sin x} \cdot \cos x+e^{\sin x} \sec x \tan x \\ & \Rightarrow \frac{d m}{d x}=e^{\sin x}\left[1+\frac{\sin x}{\cos ^2 x}\right] \\ & \Rightarrow \frac{d m}{d x}=\frac{e^{\sin x}}{\cos ^2 x}\left[\cos ^2 x+\sin x\right] \end{aligned}Differentiationofoption(a)isDifferentiation of option (a) is\begin{aligned} & =\frac{e^{\sin x}}{\cos ^2 x}\left[x \cos ^3 x+\cos ^2 x+\cos ^2 x+\sin x\right] \\ & =\frac{e^{\sin x}}{\cos ^2 x}\left[x \cos ^3 x+2 \cos ^2 x+\sin x\right] \end{aligned}Differentiationofoption(b)isDifferentiation of option (b) is\begin{aligned} & =\frac{e^{\sin x}}{\cos ^2 x}\left[x \cos ^3 x+\cos ^2 x-\cos ^2 x-\sin x\right] \\ & =\frac{e^{\sin x}}{\cos ^2 x}\left[x \cos ^3 x-\sin x\right] \end{aligned}$∴\therefore Option (2) is correct.
Practice Indefinite Integration on Quantrex Academy →

More from Indefinite Integration

Passage: Let ∫( θ\,dθ)/((2+ θ)(3+4 θ))=A |2+ θ|+B |3+4 θ| . Question: What is the value… NDA 2026Passage: Let ∫( θ\,dθ)/((2+ θ)(3+4 θ))=A |2+ θ|+B |3+4 θ| . Question: What is the value… NDA 2026What is ∫ dx 10^x + 10^ -x equal to? NDA 2025Consider the following for the two (02) items that follow: Let the function y = (1 - x)^… NDA 2025For the following two (02) items: Let u = ∫ e^x x\, dx and v = ∫ e^x x\, dx . Consider… NDA 2025For the following two (02) items: Let u = ∫ e^x x\, dx and v = ∫ e^x x\, dx . What is u +… NDA 2025Let ∫ d x x+1 - x-1 =α(x+1)^ (3)/(2) +β(x-1)^ (3)/(2) +c What is the value of β ? NDA 2024Paragraph: Let 2 ∫ x^2-1 x^2+1 d x=U(x) V(x)-3 \ U(x)+V(x)\ +c Question: What is U(x)… NDA 2024Paragraph: Let 2 ∫ x^2-1 x^2+1 d x=U(x) V(x)-3 \ U(x)+V(x)\ +c Question: What is… NDA 2024Given that ∫ (3 x+4 x)/(2 x+5 x) d x=(α x)/(29)+(β)/(29) |2 x+5 x|+c What is the value of… NDA 2024Given that ∫ (3 x+4 x)/(2 x+5 x) d x=(α x)/(29)+(β)/(29) |2 x+5 x|+c What is the value of… NDA 2024Let ∫ d x x+1 - x-1 =α(x+1)^ (3)/(2) +β(x-1)^ (3)/(2) +c What is the value of α ? NDA 2024Paragraph: Let f(x)=P e^x+Q e^ 2 x +R e^ 3 x , where P, Q, R are real numbers. Further… NDA 2023Paragraph: Let f(x)=P e^x+Q e^ 2 x +R e^ 3 x , where P, Q, R are real numbers. Further… NDA 2023What is ∫(x^x)^2(1+ x) d x equal to? NDA 2022What is ∫ e^ x (1+ x+x x) d x equal to? NDA 2022 Full Indefinite Integration list Indefinite Integration JEE Maths PYQsJEE Mathematics PYQs All NDA PYQs