If sin 3A = 3/5, find the values of cos 3A and tan 3A.
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Correct answer: D
Explanation
Given:
sin 3A = 3/5
By the formula:
sin²θ + cos²θ = 1
tanθ = sinθ / cosθ
sin 3A = 3/5
cos 3A
= √(1 − sin²3A)
= √(1 − (3/5)²)
= √(1 − 9/25)
= √(16/25)
= 4/5
tan 3A = sin 3A / cos 3A
= (3/5) / (4/5)
= 3/4
cos 3A = 4/5, tan 3A = 3/4