Question

(sin 120° / 16 cos 15°. cos 30°. cos 120°. cos 240°)² is​

Answer 1

Step-by-step explanation:

sin120

∘

cos150

∘

−cos240

∘

sin330

∘

=sin(90+30).cos(180−30)−cos(180+60).sin(360−30)

=cos30.(−cos30)−(−cos60).(−sin30)

=(

2

3

)(−

2

3

)−(−

2

1

)(−

2

1

)

=−

4

3

−

4

1

=−1