Question

Sin(40-a).cos(20-a) + cos(40-a).sin(20-a) =?

Answer 1

what question I cannot understand it

Answer 2

Answer:

√3/2

Step-by-step explanation:

Here applying the formula sinA.cosB + cosA.sinB = sin (A+B)

=sin (40°+A+(20°-A))

=sin 40°+A+20°-A)

=sin 60°

=√3/2