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 topic in other shifts

All Trigonometric Identities questions

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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 42 of the 174 JEE Main shifts held from 2017 to 2026.