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Prove this trigonometric identity
sin ​3x/sin x - cos 3x/cos x =2

1 Answer

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Explanation:

LHS= sin 3x/sin x - cos 3x/cosx

Taking LCM,

=sin3xcosx- cos3xsinx

sinxcosx

=sin(3x-x)

sinxcosx

= 2sin2x

2sinxcosx

= 2sin2x

sin2x

=2

= RHS.

Proved.

User Iamkeir
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