Question

sin 25 cos 65° + cos 25° sin 65°
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Answer 1

Sin 25° cos 65°+ cos 25° sin 65°

=(sin25°) {cos(90°-25°)} + cos 25 °

{sin (90°- 25°)}

=(sin25°) (sin25°) + (cos 25°) (cos25°)

= sin square 25° + cos square 25°

= 1(As sin square A +cos square A=1)