SOLUTION: what is the exact value if 0 < x < pi/2 and 0 < y < pi/2, of the cos (x+y) if the tan x = 5/3 and the sin y= 1/3

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Question 748244: what is the exact value if 0 < x < pi/2 and 0 < y < pi/2, of the cos (x+y) if the tan x = 5/3 and the sin y= 1/3
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
what is the exact value if 0 < x < pi/2 and 0 < y < pi/2, of the cos (x+y) if the tan x = 5/3 and the sin y= 1/3
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tanx=5/3

cos(x)=1/sec(x)=3/√34)
sin(x)=5/√34)
..
sin(y)=1/3
cos%28y%29=sqrt%281-sin%5E2%28y%29%29=sqrt%281-1%2F9%29=sqrt%288%29%2F3
...
cos(x+y)=cos(x)cos(y)-sin(x)sin(y)=[3/√34*√8/3]-[5/√34*/3)]