Question

Cos120+cos180+cos30+cos270=?

Answer 1

Cos(90+30)+cos180+cos30+cos270=sin30+cos180+cos30+cos270=1/2-1+((корень из 3)/2)+0=((корень из 3)-1)/2

Answer 2

Ответ cos600..............

Answer 3

Let's break down the calculation:

1. cos(120°) = -0.5
2. cos(180°) = -1
3. cos(30°) = √3/2
4. cos(270°) = 0

Now let's add them up:

-0.5 + (-1) + (√3/2) + 0 = -1.5 + √3/2 ≈ -0.13397

So, cos(120°) + cos(180°) + cos(30°) + cos(270°) is approximately equal to -0.13397.