document.write( "Question 297915: Find the exact value of the trigonometric function given that sin(u) = 12/13 and cos(v) = -4/5. (Both u and v are in Quadrant II.) \r
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Algebra.Com's Answer #214466 by Fombitz(32388)\"\" \"About 
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\"cos%28v-u%29+=+cos%28v%29%2Acos%28u%29+%2B+sin%28x%29%2Asin%28y%29+\"
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\n" ); document.write( "\"sin%28u%29+=+12%2F13\"
\n" ); document.write( "\"sin%5E2%28u%29%2Bcos%5E2%28u%29=1\"
\n" ); document.write( "\"%2812%2F13%29%5E2%2Bcos%5E2%28u%29=1\"
\n" ); document.write( "\"144%2F169%2Bcos%5E2%28u%29=169%2F169\"
\n" ); document.write( "\"cos%5E2%28u%29=%28169-144%29%2F169\"
\n" ); document.write( "\"cos%5E2%28u%29=25%2F169\"
\n" ); document.write( "\"cos%28u%29=0+%2B-+5%2F13\"
\n" ); document.write( "Quadrant II
\n" ); document.write( "\"cos%28u%29+=+-5%2F13\"
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\n" ); document.write( "\"cos%28v%29=-4%2F5\"
\n" ); document.write( "\"sin%5E2%28v%29+%2Bcos%5E2%28v%29=1\"
\n" ); document.write( "\"sin%5E2%28v%29%2B%28-4%2F5%29%5E2=1\"
\n" ); document.write( "\"sin%5E2%28v%29%2B%2816%2F25%29=25%2F25\"
\n" ); document.write( "\"sin%5E2%28v%29=%2825-16%29%2F25\"
\n" ); document.write( "\"sin%5E2%28v%29=9%2F25\"
\n" ); document.write( "\"sin%28v%29=0+%2B-+3%2F5\"
\n" ); document.write( "Quadrant II
\n" ); document.write( "\"sin%28v%29=3%2F5\"
\n" ); document.write( "Now substitute directly,
\n" ); document.write( "\"cos%28v-u%29+=+cos%28v%29%2Acos%28u%29+%2B+sin%28v%29%2Asin%28u%29+\"
\n" ); document.write( "\"cos%28v-u%29+=+-%284%2F5%29%2A%28-%285%2F13%29%29+%2B+%283%2F5%29%2A%2812%2F13%29+\"
\n" ); document.write( "\"cos%28v-u%29+=+20%2F65%2B+36%2F65+\"
\n" ); document.write( "\"cos%28v-u%29+=+56%2F65+\"
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