$\"\"$

\

Find quadrantal angle.

\

Draw a diagram to represent the terminal side is at positive side of $\"\"$ .

\

$\"\"$

\

Observe the diagram quadrantal angle is $\"\"$ or $\"\"$ .

\

$\"\"$

\

Draw a diagram to represent the terminal side is at positive side of $\"\"$ .

\

$\"\"$

\

Observe the diagram quadrantal angle is $\"\"$ or $\"\"$ .

\

$\"\"$

\

Draw a diagram to represent the terminal side is at negative side of $\"\"$ .

\

$\"\"$

\

Observe the diagram quadrantal angle is $\"\"$ or $\"\"$ .

\

$\"\"$

\

Draw a diagram to represent the terminal side is at negative side of $\"\"$ .

\

$\"\"$

\

Observe the diagram quadrantal angle is $\"\"$ or $\"\"$ .

\

Four possible quadrantal angle are $\"\"$ , $\"\"$ , $\"\"$ and $\"\"$ .

\

$\"\"$

\

Four possible quadrantal angle are $\"\"$ , $\"\"$ , $\"\"$ and $\"\"$ .