SOLUTION: tanx=2/3 and sinx<0 what is the exact value of cosx

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Question 581579: tanx=2/3 and sinx<0 what is the exact value of cosx
Answer by lwsshak3(11628) About Me  (Show Source):
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tanx=2/3 and sinx<0 what is the exact value of cosx
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tan=opposite side/adjacent side=2/3
hypotenuse=√(2^2+3^2)=√(4+9)=√13
sin<0 in quadrants III and IV
cosx=-3/√13 in quadrant III and 3/√13 in quadrant IV