# Trig

Find the exact value of each of the following using reference angles.

a)sin 225degrees

b) cot 120degrees

1. 👍 0
2. 👎 0
3. 👁 180
1. sin 225 ---- third quad , sine is +
= -sin45 ---- 225-180 = 45
= -1/√2 or -√2/2

cot 120 ---- quad II, tan and cot are -
= -cot 60 ---- 180-120 = 60
= -1/√3 or -√3/3

1. 👍 0
2. 👎 0

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