Find the Reference Angle (20pi)/9

$\frac{20 π}{9}$

Step 1

Find an angle that is positive, less than $2 π$ , and coterminal with $\frac{20 π}{9}$ .

Subtract $2 π$ from $\frac{20 π}{9}$ .

$\frac{20 π}{9} - 2 π$

The resulting angle of $\frac{2 π}{9}$ is positive, less than $2 π$ , and coterminal with $\frac{20 π}{9}$ .

$\frac{2 π}{9}$

Step 2

Since $\frac{2 π}{9}$ is in the first quadrant, the reference angle is $\frac{2 π}{9}$ .

$\frac{2 π}{9}$