Question

Cos⁡〖3π/4〗*cos⁡〖π/4〗+sin⁡〖3π/4〗*sin⁡〖π/4〗=

Answer 1

Ответ:

cos(3п/4 -п/4) = соs(п/2)= 0

Answer 2

To simplify the expression, we can use the trigonometric identity:

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

In this case, a = 3π/4 and b = π/4. So the expression becomes:

cos(3π/4 - π/4)

Now, we know that cos(π/2) = 0. Therefore, cos(3π/4 - π/4) = cos(π/2) = 0.

So the simplified expression is 0.