posted by kelly .
Use the even odd properties to find the exact value of the expression. It may be helpful to draw the unit circle graph sin(-pi)
The even-odd property for sine states that sin(-x) = -sin(x).
sin(-pi) = -sin(pi)
The point on the unit circle at pi (or 180 degrees) is (-1, 0). Sine corresponds to the y-value, so sine at that point is 0.
-sin(pi) = -0 = 0