Question

Write a value of sinAcos(90-A) +cosAsin(90-A)

Answer 1

The value is 1 because sin square +cos square =l

Answer 2

cos(90-A)=sinA
and
sin(90-A)=cosA
In above question
sinA*cos(90-A)+cosA*sin(90-A)
sinA*sinA+cosA*cosA
sin2A+cos2a. ............. (1)
[sin2x+cos2x=1]
so in (1)
value is 1