WBBSEClass XMathematicsTrigonometric Ratios And Trigonometric Identities01 Mark2024 Moderate

QQuestion

If sin (θ – 30°) = 1\over2, then cos θ = ____

Exam-ready answer 01 Mark

Answer

√3\over2

Explanation :

We know sin 30° = 1\over2

So, sin(θ − 30°) = 1\over2

⇒ sin(θ − 30°) = sin 30°

⇒ θ − 30° = 30°

⇒ θ = 60°.

Now, cos θ = cos 60° = √3\over2

Was this answer helpful?