SOLUTION: Given that sinx=3/5 and it is in quadrant 1. Find sin2x+cos2x

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Question 992754: Given that sinx=3/5 and it is in quadrant 1. Find sin2x+cos2x
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Hi there,
If sin x = 3/5
cos x = 4/5
tan x = 3/4
..........
sin 2x = 2 sin x cos x
sin 2x = 2 (3/5)(4/5)
sin 2x = 24/25
..........
cos 2x = 2 cos^2 x - 1
cos 2x = 2(4/5)^2 - 1
cos 2x = 2(16/25) - 1
cos 2x = 32/25 - 1
cos 2x = 32/25 - 25/25
cos 2x = 7/25
..........
Hope this helps :-)