Question

if A=60,B=30 VERIFY THAT COS (A+B)/SIN A SIN B+1= TAN A TAN B SIN (A-B)/COS A COS B=TAN A-TAN B

Answer 1

In case you aren't given values of A and B, this is how you can do it:

LHS=sin(A+B)cosAcosB

=sinAcosB+cosAsinBcosAcosB

=sinAcosA+sinBcosB

=tanA+tanB

=RHS

Hope it helps!