<PRE><B>Question 582435</B>
If A is a positive acute angle and sin A = the square root of 5/3 what is cos A
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A is in Q1.
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sin(A) = sqrt(5)/3 
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But sin(A) = y/4
So, y = sqrt(5) and r = 4
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Then x = sqrt[r^2-y^2] = sqrt[16-5] = sqrt(11)
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cos(A) = x/r = sqrt(11)/4
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Cheers,
Stan H.
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