Question

If tan(A + B) = −2 and tan B = 3, find tan A.

Answer 1

Tan a =1

Explanation:

TRIG identity:

Tan ( a+b) = (tan a + tan b )/ (1 - tan a tan b) Sub in the given values

-2 = ( tan a + 3) / ( 1 - 3 tan a)

-2 + 6 tan a = tan a + 3

5 tan a = 5

tan a = 1

Answer 2

Tan a is -5
Sub in the value for b