JEE Main 2025 — Trigonometric Ratios & Identities Question with Solution
JEE Main 2025 (29 Jan Shift 2)
Question
If , then is equal to :
Choose an option
Show full solutionCorrect option: D
Correct answer
D2
Step-by-step explanation
$\begin{aligned}
& \sin x+\sin ^2 x=1 \\
& \Rightarrow \sin x=\cos ^2 x \Rightarrow \tan x=\cos x
\end{aligned}$
Given expression
$\begin{aligned}
& =2 \cos ^{12} x+6\left[\cos ^{10} x+\cos ^8 x\right]+2 \cos ^6 x \\
& =2\left[\sin ^6 x+3 \sin ^5 x+3 \sin ^4 x+\sin ^3 x\right] \\
& =2 \sin ^3 x\left[(\sin x+1)^3\right] \\
& =2\left[\sin ^2 x+\sin x\right]^3 \\
& =2
\end{aligned}$
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This is a previous-year question from JEE Main 2025, covering the Trigonometric Ratios & Identities chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.