Question

If A = 30°
I find the value af Cbs4A- Sin4A
slove that-1-Cos2A/Sin2A=tanA
​

Answer 1

Answer:

1-cos2A/sin2A

=(1-cos^2 A+sin^2 A)/(2sinAcos)

=(sin^2 A+sin^2A)/2sinAcosA

=2sin^2 A/2sinAcos^2 A

=sinA/cosA

=tanA

...proved