JEE Main 2021 · MathsNumerical answerNumerical valueMediumMulti-step

JEE Main 4 August 2021, Shift 1, Maths Q90

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

\tan A

is equal to the integral solution of the inequality

4x^2-24x+35<0

and

\sin B

is equal to the slope of the angle bisector of the second quadrant, then

40\sin(A+B)\sin(B-A)

is ________.

Official answer

NTA final key.

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

Same idea in other shifts

Asked 5× in all

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30 Jan 2024, Shift 2 · Q11For $\alpha, \beta \in (0, \pi/2)$ , let $3\sin(\alpha + \beta) = 2\sin(\alpha - \beta)$ and a real number $k$ be such that…MediumSingle correct
28 Jun 2022, Shift 2 · Q20If $\cot\alpha=1$ and $\sec\beta=-\frac{5}{3}$ , where $\pi<\alpha<\frac{3\pi}{2}$ and $\frac{\pi}{2}<\beta<\pi$ , then the value of…EasySingle correct
8 Jan 2020, Shift 2 · Q75If $\frac{\sqrt{2}\sin\alpha}{\sqrt{1 + \cos 2\alpha}} = \frac{1}{7}$ and $\sqrt{\frac{1 - \cos 2\beta}{2}} = \frac{1}{\sqrt{10}}$ ,…MediumNumerical 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.