Question

if cos 9a = sina and 9a = 90 degrees then find the value of tan 5a​

Answer 1

Answer:

1

Step-by-step explanation:

cos 9A = sin A

cos 9A = cos (90-A)

9A = 90 - A

10A = 90

A = 9

So tan 5A = tan 45 = 1

Answer 2

Answer:

Given that

cos9A = sinA

We know that

sinA = cos(90° - A)

cos9A = cos(90° - A)

By comparing

9A = 90° - A

9A + A = 90°

10A = 90°

A = 90°/10

A = 9°

To find:

tan5A

Substituting A = 9°

tan5(9)

tan 45° = 1

Hence the value of tan5A = tan45° = 1