Tan a = x , maka sin 2a =...

Tan a = depan / samping = x / 1

samping = ... ?

Misalkan :
=> Depan = A
=> Samping = B
=> Miring = C

C^2 =A^2 + B^2
C^2 = x^2 + 1^2
C = Vx^2 + 1

Sin a = depan / miring
Sin a = x/Vx^2 +1

sin 2a = 2 ( x / Vx2 +1
sin 2a = 2x / Vx^2 + 1

Nb = V = akar