JEE Main 2019MathematicsTrigonometric EquationsEasyMCQ

JEE Main 2019 — Trigonometric Equations Question with Solution

JEE Main 2019 (09 Jan Shift 2)

Question

If 0≤x<π2, then the number of values of x for which sinx-sin2x+sin3x=0, is:

Choose an option

Show full solutionCorrect option: C
Correct answer
C2

Step-by-step explanation

sinx-sin2x+sin3x=0

⇒sinx+sin3x-sin2x=0

⇒2sin2 x .cosx-sin2x=0

⇒sin2x=0 or cosx=12

⇒2x=0 or x=π3

⇒x=0 or  x=π3

∴ Number of solutions =2

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About this question

This is a previous-year question from JEE Main 2019, covering the Trigonometric Equations chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.