If sin (θ – 30°) = 1\over2, then cos θ = ____
WBBSE
Class X
Mathematics
Trigonometric Ratios And Trigonometric Identities
01 Mark
2024
√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
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