Question

cos60 x cos30 + sin60 x sin30

solve please...

Answer 1

Cos60×Cos30 + Sin60× Sin30.

= 1/2 × root 3/2 + root 3/2 × 1/2

= root 3/4 + root 3/4

= 1 .

Answer 2

Hello friend
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In the example

Given:

cos 60° = 1/2

cos 30° = √3/2

sin 60° = √3/2

sin 30° = 1/2

So let's put the given values.

$\frac{1}{2} \times \frac{ \sqrt{3} }{2} + \frac{ \sqrt{3} }{2} \times \frac{1}{2} \\ \\ = \frac{1 \times \sqrt{3} }{2 \times 2} + \frac{ \sqrt{3} }{2} \times \frac{1}{2} \\ \\ = \frac{ \sqrt{3} }{4} + \frac{ \sqrt{3} }{4} \\ \\ = \frac{2 \sqrt{3} }{4} \\ \\ = \frac{ \sqrt{3} }{2}$

I hope this will helps you..

Thanks.