### Home > CCA2 > Chapter 9 > Lesson 9.1.1 > Problem9-11

9-11.

Solve each equation for $0 ≤ θ ≤ 360$. You may need your calculator, but remember that your calculator only gives one answer. Most of these problems have more than one answer. Think about all four quadrants.

1. sin $θ = 0.5$

Where is the sin$θ = 0.5$? Remember sin is the $y$-value. What would $θ$ be at those places?

$θ = 30° θ = 150°$

1. cos $θ = -0.5$

Where is the cos$θ = -0.5$? Remember cos is the $x$-value. What would $θ$ be at those places?

1. $4$ tan $θ- 4 = 0$

Solve for the tan$θ$. Draw a unit circle. Where is the tan$θ$ of that value?

1. $3$ sin$^2$ $θ = 1$

Use your calculator to get one of the values. Then use symmetry to get the other $3$ values. There are $4$ values because when you take the square root of both sides the answer would be plus or minus!