Chapter 13 - The Trigonometric Functions - 13.1 Definitions of the Trigonometric Functions - 13.1 Exercises - Page 678: 23

$-,-,+,+,-,-$

- In th third quadrant where $\theta\in [\pi,\frac{3\pi}{2}]$, the sine is $-$ and cosine is $−$. - Since tangent is the ratio of sine to cosine, the tangent is $+$ in the third quadrant. - Since cotangent is 1 over tangent, the cotangent is $+$ in the third quadrant. - Since secant is 1 over cosine, the secant is $-$ in the third quadrant. - Since cosecant is 1 over sine, the cosecant is $-$ in the third quadrant.