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If tan(theta) = 3/4 and theta is an acute angle, find cos(theta)

User Benja
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sin t / cos t = 3 / 4
4 sin t = 3 cos t
sin t = 3 cos t / 4
sin² t + cos² t = 1
( 3 cos t / 4 )² + cos² t = 1
9 cos² t / 16 + cos² t = 1 / · 16
9 cos² t + 16 cos² t = 16
25 cos² t = 16
cos ² t = 16/25
Answer:
cos t = 4 / 5
User Davidjnelson
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