Question

If A is an acute angle with cos A= 5/7 & B is an obtuse angle with sin B=1/5, find values of sin (A-B) and cos(A-B)

Answer 1

\[\sin(a-b) = \sin a \cos b - \sin b \cos a\]
\[\cos(a-b) = \cos a \cos b + \sin a \sin b\]

Answer 2

ok..
what shld I do next

Answer 3

@dumbcow