Question

sin36º.cos9° +cos36º. sin9º is equal to-
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Answer 1

Step-by-step explanation:

by the formula,

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

so,

sin 36°•cos9°+cos36°•sin9°

=sin(36+9)

= sin 45°

=1/√2

$= \frac{1}{ \sqrt{2} }$