ExamBro
ExamBro
JEE Mains · Maths · STD 12 - 7.2 definite integral

माना \(\left(0, \frac{\pi}{2}\right)\) में \(f\) एक अवकलनीय फलन है।यदि \(\int \limits_{\cos x}^1 t^2 f(t) d t=\sin ^3 x+\cos x\) है, तो \(\frac{1}{\sqrt{3}} f ^{\prime}\left(\frac{1}{\sqrt{3}}\right)\) बराबर है:

  1. A \(6-9 \sqrt{2}\)
  2. B \(\frac{9}{\sqrt{2}}-6\)
  3. C \(\frac{9}{2}-6 \sqrt{2}\)
  4. D \(6-\frac{9}{\sqrt{2}}\)
Verified Solution

Answer & Solution

Correct Answer

(D) \(6-\frac{9}{\sqrt{2}}\)

Step-by-step Solution

Detailed explanation

\(\int\limits_{\cos x}^{1} t^{2} f(t) d t=\sin ^{3} x+\cos x-1\) Calculation for option differentiating both sides \(-\cos ^{2} x f(\cos x) \cdot(-\sin x)=3 \sin ^{2} x \cdot \cos x-\sin x\) \(\Rightarrow f (\cos x )=3 \tan x -\sec ^{2} x\)…
Same subject
Explore more questions on app
From JEE Mains
Explore more questions on app