JEE 2023 — Mathematics PYQ
JEE | Mathematics | 2023The value of the integral ∫−π/4π/42−cos2xx+π/4dx is:
Choose the correct answer:
- A.
123π2
- B.
63π2
63π2
Explanation
Solution
Integral ko do bhagon mein baantein: I=∫−π/4π/42−cos2xxdx+∫−π/4π/42−cos2xπ/4dx.
Pehla bhag odd function hai, isliye uska value 0 ho jayega.
Doosra bhag even function hai:
I=2×4π∫0π/42−cos2x1dx=2π∫0π/41+3tan2xsec2xdx.
Substitute karein 3tanx=t:
I=23π∫031+t21dt=23π[tan−1t]03=23π×3π=63π2.
Correct Option: (2)
Explanation
Solution
Integral ko do bhagon mein baantein: I=∫−π/4π/42−cos2xxdx+∫−π/4π/42−cos2xπ/4dx.
Pehla bhag odd function hai, isliye uska value 0 ho jayega.
Doosra bhag even function hai:
I=2×4π∫0π/42−cos2x1dx=2π∫0π/41+3tan2xsec2xdx.
Substitute karein 3tanx=t:
I=23π∫031+t21dt=23π[tan−1t]03=23π×3π=63π2.
Correct Option: (2)

