document.write( "Question 1179610: Find the exact value of the trigonometric function given that sin u = -3/5 and cos v = -7/25 (Both u and v are in Quadrant III.)
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Algebra.Com's Answer #809180 by MathLover1(20850)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( " Find the exact value of the trigonometric function given that \r
\n" ); document.write( "\n" ); document.write( "\"sin%28+u%29+=+-3%2F5\" and
\n" ); document.write( "\"cos+%28v+%29=+-7%2F25\"\r
\n" ); document.write( "\n" ); document.write( " (Both u and v are in Quadrant III.)\r
\n" ); document.write( "\n" ); document.write( "first find \"+cos%28u%29\" and \"sin%28+v%29+\"\r
\n" ); document.write( "\n" ); document.write( "if \"sin%28+u%29+=+-3%2F5\" then \"opp=3\" and \"hyp=5\"\r
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\n" ); document.write( "\n" ); document.write( "use Pythagorean theorem to find \"adj\" side\r
\n" ); document.write( "\n" ); document.write( "\"adj=sqrt%285%5E2-3%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"adj=sqrt%2825-9%29\"\r
\n" ); document.write( "\n" ); document.write( "\"adj=sqrt%2816%29\"\r
\n" ); document.write( "\n" ); document.write( "\"adj=4\" or\"adj=+-4\"\r
\n" ); document.write( "\n" ); document.write( "since \"u+\" in Quadrant III, sine and cosine are negative, so use \"adj=-4\"\r
\n" ); document.write( "\n" ); document.write( "and\"+cos%28u%29=-4%2F5\"\r
\n" ); document.write( "\n" ); document.write( "if \"cos+%28v+%29=+-7%2F25\" then \"adj=7\" and \"hyp=25\"\r
\n" ); document.write( "\n" ); document.write( "\"opp=sqrt%2825%5E2-7%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"opp=sqrt%28576%29\"\r
\n" ); document.write( "\n" ); document.write( "\"opp=24\" or \"opp=-24\"...in Quadrant III sine and cosine are negative\r
\n" ); document.write( "\n" ); document.write( "\"sin%28v%29=-24%2F25\"\r
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\n" ); document.write( "\n" ); document.write( "since \"sin%28+u%29+=+-3%2F5\",\"+cos%28u%29=-4%2F5\", \"sin%28v%29=-24%2F25\", \"cos+%28v+%29=+-7%2F25\", then,\r
\n" ); document.write( "\n" ); document.write( "\"sin%28u%2Bv%29+=sin%28u%29+cos%28v%29+%2Bcos%28u%29+sin%28v%29+\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%28u%2Bv%29+=%28-3%2F5%29+%28-7%2F25%29+%2B++%28-4%2F5%29%28-24%2F25%29\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%28u%2Bv%29+=21%2F125%2B++96%2F125\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%28u%2Bv%29+=117%2F125\"\r
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