Prove this identity sin(2A)=2sinAcosA.

1 answer:

34kurt3 years ago

7 0

The solution for proving the identity is as follows:

sin(2A) = sin(A + A)
As sin(a + b) = sinacosb + sinbcosa,
sin(A + A) = sinAcosA + sinAcosA

Therefore, sin(2A) = 2sinAcosA

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