Home > Resources > Homework > Math > Unit Circle

Find the value of $ an(θ) $ using the unit circle when $ θ $ is in the third quadrant

Answer 1

Abigail Nelson

Alex Thompson

To find the value of $ \tan(θ) $ using the unit circle, we need to determine the coordinates where $ θ $ intersects the unit circle in the third quadrant.

In the third quadrant, both the x and y coordinates are negative. Suppose $ θ = 225° $ (or $ \frac{5π}{4} $ in radians). In this case, the coordinates on the unit circle are $ ( -\frac{\sqrt{2}}{2}, -\frac{\sqrt{2}}{2} ) $.

The tangent of $ θ $ is given by the ratio of the y-coordinate to the x-coordinate:

$ \tan(225°) = \frac{y}{x} = \frac{-\frac{\sqrt{2}}{2}}{-\frac{\sqrt{2}}{2}} = 1 $

Answer 2

Alex Thompson

Lily Perez

To determine $ an(θ) $ using the unit circle in the third quadrant, we identify the coordinates for an angle in this quadrant. For $ θ = 240° $ (or $ frac{4π}{3} $ radians), the corresponding coordinates are $ ( -frac{1}{2}, -frac{sqrt{3}}{2} ) $.

The tangent value is calculated as:

$ an(240°) = frac{y}{x} = frac{-frac{sqrt{3}}{2}}{-frac{1}{2}} = sqrt{3} $

Answer 3

Amelia Mitchell

Thomas Walker

To find $ an(θ) $ in the third quadrant using the unit circle, take $ θ = 210° $ (or $ frac{7π}{6} $ radians). The coordinates are $ ( -frac{sqrt{3}}{2}, -frac{1}{2} ) $.

Thus,

$ an(210°) = frac{y}{x} = frac{-frac{1}{2}}{-frac{sqrt{3}}{2}} = frac{1}{sqrt{3}} $