### Home > PC3 > Chapter 8 > Lesson 8.3.2 > Problem8-100

8-100.

For each of the trigonometric functions below, decide if they are even, odd, or neither. Then use the even/odd properties of each function to complete each equation below.

Review your work from parts (d) through (f) of problem 8-89.
An angle measure of $2π − x = x$ in the unit circle.

1. $\sin\left(–x\right) =\underline{ \ \ \ \ \ \ \ }$

If $\sin\left(−x\right) = \sin\left(x\right)$, then sine is an even function.
If $\sin\left(−x\right) = −\sin\left(x\right)$, then sine is an odd function.

1. $\cos\left(–x\right) =\underline{ \ \ \ \ \ \ \ }$

Is the graph of $y = \cos\left(x\right)$ symmetric across the $y$-axis, or is it symmetric about the origin?

1. $\tan\left(–x\right) =\underline{ \ \ \ \ \ \ \ }$

Is the sign of tangent the same in Quadrants I and II or is the sign the same in Quadrants I and III?