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SSC CHSL 2020 PYQ — Question 52

SSC CHSL - 20th October 2020 - Shift 1 • Quantitative Aptitude • Q52

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If xSin3θ + yCos3θ = Sinθ Cosθ and xSinθ = yCosθ, then find the value of x2 + y2.

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Correct answer: D

Explanation

The correct answer is option 4 i.e 1

We have,

⇒ xSinθ = yCosθ

⇒ y = xTanθ

⇒ xSin3θ + yCos3θ = Sinθ.Cosθ

⇒ xSin3θ + (xTanθ)Cos3θ = Sinθ Cosθ

⇒ xSin2θ + xCos2θ = Cosθ

⇒ x = Cosθ

⇒ y = Sinθ & x = Cosθ

⇒  x2 + y2 = Sin2θ + Cos2θ = 1