Question

How do you find sin20°cos40°+cos20°sin40°

Answer 1

That's of course the sum angle formula for sine

sin(a+b) = sin a cos b + cos a sin b

We have a=20° b=40°

sin 20° cos 40° + cos 20° sin 40°

= sin(20°+40°)

= sin(60°)

= √3/2

Answer: √3/2