document.write( "Question 904452: Using your knowledge of trigonometric identities, ﬁnd the exact value of sin(x+y) knowing that x and y are between 0 and π/2, that sin(x)=4/5 and that sec(y)=13/5. Your answer must be a rational number, written in the form of an irreducible fraction p/q (such as 2/3, 4/5, −1/4, etc.), with q>0. Give the integers p and q. \n" ); document.write( "

Algebra.Com's Answer #548698 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"1%2Fcos%28y%29+=+13%2F5\"$ , cos(y) = 5/13 and sin(y) = 12/13 $\"12+=+sqrt%28169-25%29\"$
\n" ); document.write( "sin(x) = 4/5, cos(x) = 3/5 $\"3+=+sqrt%2825-16%29\"$
\n" ); document.write( "sin(x+y) = sin(x)c0s(y)+ cos(x)sin(y) = $\"%284%2F5%29%285%2F13%29+%2B+%283%2F5%29%2812%2F13%29+=+56%2F65\"$ \n" ); document.write( "

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