Question

cos60∘×cos30∘+sin60∘×sin30∘​

Answer 1

$Answer \:$

cos 60° × cos 30° + sin 60° × sin 30° = √3/2

Let see how we can solve this.

$\large\underline{{Solution \: }}$

As we know that:

cos 60° =  1/2, cos 30° =  √3/2, sin 60° =  √3/2, sin 30° = 1/2

Substituting all the values in the given expression,

(1/2 × √3/2) + (√3/2 × 1/2)

= √3/4 + √3/4

= 2√3/4

= √3/2

Thus, (cos 60° × cos 30°) + (sin 60° × sin 30°) = √3/2

Answer 2

Answer:

Step-by-step explanation:

cos 60° × cos 30° + sin 60° × sin 30°

= cos ( 60° + 30° )

= cos 90°

= 0 is the answer.