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Friday, 9 October

JEE Main 2020 · MathsMultiple choiceSingle correctHardMulti-step

JEE Main 8 January 2020, Shift 1, Maths Q69

Question 69 of 75 in this shift, Maths question 19 of 25, Section A.

Let f(x)=(sin⁡(tan⁡−1x)+sin⁡(cot⁡−1x))2−1f(x)=\left(\sin(\tan^{-1}x)+\sin(\cot^{-1}x)\right)^2-1, ∣x∣>1|x|>1. If dydx=12ddx(sin⁡−1(f(x)))\dfrac{dy}{dx}=\dfrac{1}{2}\dfrac{d}{dx}\left(\sin^{-1}(f(x))\right) and y(3)=π6y(\sqrt{3})=\frac{\pi}{6}, then y(−3)y(-\sqrt{3}) is equal to :
  1. (1)−π6-\frac{\pi}{6}
  2. (2)2π3\frac{2\pi}{3}
  3. (3)5π6\frac{5\pi}{6}Official answer
  4. (4)π3\frac{\pi}{3}

Official answer

Option 3

NTA final key (Jan 2020).

Same topic in other shifts

All Inverse Trig Identities questions
  1. 4 Apr 2026, Shift 1 · Q16If y=tan⁡−1(3cos⁡x−4sin⁡x4cos⁡x+3sin⁡x)+2tan⁡−1(x1+1−x2)y=\tan^{-1}\left(\frac{3\cos x-4\sin x}{4\cos x+3\sin x}\right)+2\tan^{-1}\left(\frac{x}{1+\sqrt{1-x^2}}\right), then dydx\frac{dy}{dx}…MediumSingle correct
  2. 4 Apr 2026, Shift 2 · Q20The integral ∫01cot⁡−1(1+x+x2)dx\int_0^1\cot^{-1}\left(1+x+x^2\right)dx is equal to:HardSingle correct
  3. 5 Apr 2026, Shift 1 · Q24If π4+∑p=111tan⁡−1(2p−11+22p−1)=α\frac{\pi}{4} + \sum_{p=1}^{11} \tan^{-1}\left(\frac{2^{p-1}}{1 + 2^{2p-1}}\right) = \alpha, then tan⁡α\tan\alpha is equal to ________.MediumNumerical value
  4. 6 Apr 2026, Shift 1 · Q13Let 0<α<10<\alpha<1, β=13α\beta=\frac{1}{3\alpha} and tan⁡−1(1−α)+tan⁡−1(1−β)=π4\tan^{-1}(1-\alpha)+\tan^{-1}(1-\beta)=\frac{\pi}{4}. Then 6(α+β)6(\alpha+\beta) is equal to:MediumSingle correct
  5. 6 Apr 2026, Shift 2 · Q13If sin⁡(tan⁡−1(x2))=cot⁡(sin⁡−11−x2)\sin\left(\tan^{-1}\left(x\sqrt{2}\right)\right)=\cot\left(\sin^{-1}\sqrt{1-x^2}\right), x∈(0,1)x\in(0,1), then the value of xx is :MediumSingle correct
  6. 8 Apr 2026, Shift 2 · Q12Let α=3sin⁡−1(611)\alpha = 3\sin^{-1}\left(\frac{6}{11}\right) and β=3cos⁡−1(49)\beta = 3\cos^{-1}\left(\frac{4}{9}\right), where inverse trigonometric functions…HardTwo statements

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.