QQuestion
If tan θ cos 60° = \frac{\sqrt{3}}{2} then the value of sin(θ – 15°) is _____.
If tan θ cos 60° = \frac{\sqrt{3}}{2} then the value of sin(θ – 15°) is _____.
1\over√2.
Explanation
tan θ cos 60° = \frac{\sqrt{3}}{2}
or, tan θ × 1\over 2 = \frac{\sqrt{3}}{2}
or, tan θ = √3
or, tan θ = tan 60º
or, θ = 60º
sin(θ – 15°) = sin(60º – 15°)
= sin 45°
= 1\over√2
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