1.9 Polar, Cylindrical, and Spherical Coordinates

Polar, Cylindrical, and Spherical Coordinates

Introduction

An angle in the $xy$-plane is in standard position if the initial side of the angle is on the positive $x$-axis and is measured with the positive direction going counterclockwise.

If an angle $\theta$ is in standard position, for which quadrants will $\sin(\theta)$ be positive? For which quadrants will $\sin(\theta)$ be negative? Which angles correspond to $\sin(\theta)=0$?