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If cos(x) = Three-fourths and tan(x) < 0, what is cos(2x)?.

User PongGod
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2 Answers

4 votes

Answer:C

Step-by-step explanation:

did it on edge

User Wooters
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3 votes

Recall the double angle identity for cosine,

cos(2x) = 2 cos²(x) - 1

Then

cos(2x) = 2 (3/4)² - 1 = 1/8

User Suraj Rawat
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3.7k points