Question

-2sin(240градусов) cos(30градусов)=?

Answer 1

Sin240°= sin(180°+60°)= -sin60°= -√3/2
cos30°= √3/2
-2( -√3/2)*√3/2= 3/2= 1,5

Answer 2

To calculate the value of the expression, let's first convert the angles from degrees to radians.

240 degrees = (240 * π) / 180 = 4π/3 radians 30 degrees = (30 * π) / 180 = π/6 radians

Now we can substitute these values into the expression:

-2sin(240 degrees) cos(30 degrees) = -2sin(4π/3) cos(π/6)

Using trigonometric identities, we can simplify the expression:

sin(4π/3) = -√3/2 cos(π/6) = √3/2

Substituting these values:

-2sin(4π/3) cos(π/6) = -2(-√3/2)(√3/2) = 3

Therefore, -2sin(240 degrees) cos(30 degrees) equals 3.