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प्रश्न
Verify the following equalities:
sin 30° cos 60° + cos 30° sin 60° = sin 90°
उत्तर
sin 30° = `1/2`, cos 60° = `1/2`, cos 30° = `sqrt(3)/2`, sin 60° = `sqrt(3)/2`, sin 90° = 1
L.H.S = sin 30° cos 60° + cos 30° sin 60°
= `1/2 xx 1/2 + sqrt(3)/2 xx sqrt(3)/2`
= `1/4 + 3/4`
= `4/4`
= 1
R.H.S = sin 90° = 1
L.H.S = R.H.S
Hence it is proved.
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