Question

The expression tan (A + B) = tan (A - B) is an identity that is true for all values of A and B.
True or False
I think it is true ?

Answer 1

i also think it is true

Answer 2

but i am not quite sure

Answer 3

It's only true for particular values of B (like B = 0, B = pi/2, B = pi, etc)

In general, the equation is not an identity because if B = 1, then you can plug in values of A (like A = pi/4) and you'll find the equation is not true.