How Sin(2A) = 2SinA CosA or Sin(A) = 2Sin(A/2) Cos(A/2) ?

Derivation of 

Sin(2A) = 2 SinA CosA

or

Sin(A) = 2Sin(A/2) Cos(A/2)?

As we know that,

⇒Sin(A+B) = SinA CosB + CosA SinB

👉👉(Sin(A+B) = SinA CosB + CosA SinB)

put B= A

then,

⇒Sin(A+A) = SinA CosA + CosA SinA

  

⇒Sin(2A) = SinA CosA + SinA CosA

Hence, Sin(2A) = 2SinA CosA

⇒If angle will be halfed i.e. θ = A

⇒Hence,

      Sin(A) = 2Sin(A/2) Cos(A/2)