Question

sin(90°-theta) cos theta+cos(90°-theta) sintheta=​

Answer 1

Solution :-

Here we have

• sin(90 - ∅).cos∅ + cos (90 - ∅).sin∅

We know

• sin(90 - ∅) = cos∅

• cos(90 - ∅) = sin∅

Then

= sin(90 - ∅).cos∅ + cos (90 - ∅).sin∅

= cos∅.cos∅ + sin∅.sin∅

= cos²∅ + sin²∅

= 1