Question

find the value of sin15 degree.

Answer 1

Sin 15°=Sin(45°-30°)
=Sin 45°Cos 30°-Cos 45°Sin 30°
=1/√2 ×√3/2-1/√2×1/2
=√3/2√2-1/2√2
=√3-1/2√2

Answer 2

Hi ,

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Sin ( A - B ) = sinAcosB - sinBcosA

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Sin 15°

= Sin ( 45 - 30 )

= Sin 45°cos 30° - sin 30° cos 45°

= ( 1/√2 ) ( √3/2 ) - ( 1/2 ) ( 1/√2 )

= ( √3/2√2 ) - ( 1/ 2√2 )

= ( √3 - 1 ) / 2√2

I hope this helps you.

:)