Question

prove that sin2 thetta= 2 sinthetata cos thetta​

Answer 1

Prove that :-

$\tt \:  sin \: 2 \: \theta = 2 \: sin\: \theta \: cos\: \theta$

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$\large\underline\purple{\bold{Solution :- }}$

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☆ We know that

$\tt \:  ⟼ \: sin \: (x + y) \: = \: sinx \: cosy + siny \: cosx$

$\tt \:  ⟼ \: Put \: x = \: \theta \: and \: y = \: \theta$

$\tt \:  : \: ⟼ \: \therefore \: sin(\: \theta + \: \theta) = sin\: \theta \: cos\: \theta \: + \: cos\: \theta \: sin\: \theta$

$\tt \:  ⟼ \: \therefore \: sin2\: \theta \: = 2 \: sin\: \theta \: cos\: \theta$

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$\large{\boxed{\boxed{\bf{Hence, Proved}}}}$

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