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प्रश्न
If A = B = 45° ,
show that:
sin (A - B) = sin A cos B - cos A sin B
उत्तर
Given that A = B = 45°
LHS = sin (A – B)
= sin ( 45° – 45°)
= sin 0°
= 0
RHS = sin A cos B – cos A sin B
= sin 45° cos 45° – cos 45° sin 45°
= `(1)/(sqrt2) (1)/(sqrt2) – (1)/(sqrt2) (1)/(sqrt2)`
= 0
LHS = RHS
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