Question

What are the sine, cosine, and tangent of Θ = 3 pi over 4 radians?

Answer 1

What is the reference angle for \(\frac{3\pi}{4}\)?

Answer 2

doesn't give one

Answer 3

It does have one.

Answer 4

3pi over 4 radians?

Answer 5

Do you know what a reference angle is?

Answer 6

no

Answer 7

A reference angle is the Quadrant I angle that corresponds to the angle you are given.
If you have an angle in Quadrant II, subtract it from 180°.
If your angle is in Quadrant III, subtract 180° from that.
If your angle is in Quadrant IV, subtract it from 360°.

Example: if you get 150° then you would subtract it: 180°-150° = 30° which is \(\frac{\pi}{6}\) in radians.

Answer 8

Maybe putting everything in degrees will make it easier. What is \(\frac{3\pi}{4}\) in degrees?

Answer 9

\[\frac{3\pi}{4}\times\frac{180}{\pi}\rightarrow\frac{3\cancel{\pi}}{4}\times\frac{180}{\cancel{\pi}}\rightarrow\frac{3\times180}{4}=\]

Answer 10

What's the degree form?

Answer 11

135? @kittiwitti1

Answer 12

\(\color{blue}{\text{Originally Posted by}}\) @katecc379
135? @kittiwitti1
\(\color{blue}{\text{End of Quote}}\)

Yeah. Now which quadrant is that in?