If cos(2x) = tan^2(y), show that cos(2y) = tan^2(x).

We are given that:

Now we are asked to show that:

We know that:

Hence using equation (1) we get:

Also we know that:

and

so using above two formula in equation (2) we get:

( since we know that:

)

Hence we have proved that:

the answer would be c:   ax + b = ax + c

step-by-step explanation: