Question

Sec (theta)-tan (theta)=a+1/a-1 , find cos(theta)=?

Answer 1

Since, Sec∆=1/cos∆

& Tan∆ = Sin∆/Cos∆

Sec∆-Tan∆=(1/cos∆)-(Sin∆/Cos∆)

a+1/a-1=(1-Sin∆) /Cos∆

There fore cos∆ = a-1.

Where ∆ = theta.