JEE Main 2023 · MathsMultiple choiceSingle correctHardApplication

JEE Main 8 April 2023, Shift 2, Maths Q19

Question 19 of 90 in this shift, Maths question 19 of 30, Section A.

The value of

36(4\cos^2 9^\circ - 1)(4\cos^2 27^\circ - 1)(4\cos^2 81^\circ - 1)(4\cos^2 243^\circ - 1)

(1)18
(2)27
(3)36Official answer
(4)54

Official answer

Option 3

NTA final key.

Chapter: Trigonometric Functions
Topic: Trigonometric Identities
Idea tested: Triple Angle Formulas

Same idea in other shifts

Asked 2× in all

17 Mar 2021, Shift 2 · Q82Let $\tan\alpha$ , $\tan\beta$ and $\tan\gamma$ ; $\alpha, \beta, \gamma\neq\frac{(2n-1)\pi}{2}$ , $n\in\mathbf{N}$ be the slopes of three…HardNumerical value

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.