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Given tantheta = 4/3 and pi < theta < 3pi/2; find cos2theta

Given tantheta = 4/3 and pi < theta < 3pi/2; find cos2theta-example-1

2 Answers

5 votes

Answer:

D

Explanation:

edge

User LepardUK
by
6.5k points
5 votes

Answer:

d. -7/25

Explanation:

π<θ<3π/2 in third quadrant

tanθ = 4/3

sinθ = - 4/5

cosθ = - 3/5

cos 2θ = cos²θ - sin²θ = (- 3/5)² - (- 4/5)² = 9/25 - 16/25 = - 7/25

User Archgl
by
7.1k points
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