document.write( "Question 1179362: Find the exact value of the trigonometric function given that sin u = -12/13 and cos v = 24/25. (Both u and v are in Quadrant IV) a)sin (u+v) b)cos(v-u) c)tan(u-v) \n" ); document.write( "
Algebra.Com's Answer #808904 by MathLover1(20849)\"\" \"About 
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\n" ); document.write( "Find the exact value of the trigonometric function given that \r
\n" ); document.write( "\n" ); document.write( "\"sin+%28u%29+=+-12%2F13\" and \"cos+%28v+%29=+24%2F25\"\r
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\n" ); document.write( "\n" ); document.write( "using Pythagorean identity to find \"cos%28u%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"sin%5E2+%28u%29+%2Bcos%5E2%28u%29=1\"\r
\n" ); document.write( "\n" ); document.write( "\"%28+-12%2F13%29%5E2+%2Bcos%5E2%28u%29=1\"\r
\n" ); document.write( "\n" ); document.write( "\"cos%5E2%28u%29=1-%28+-12%2F13%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"cos%5E2%28u%29=1-144%2F169\"\r
\n" ); document.write( "\n" ); document.write( "\"cos%5E2%28u%29=25%2F169\"\r
\n" ); document.write( "\n" ); document.write( "\"cos%28u%29=sqrt%2825%2F169%29\"\r
\n" ); document.write( "\n" ); document.write( "\"cos%28u%29=5%2F13\" or \"cos%28u%29=+-5%2F13+\"\r
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\n" ); document.write( "\n" ); document.write( " In the fourth quadrant, the values for cos are positive only, so use \"cos%28u%29=+5%2F13+\"\r
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\n" ); document.write( "\n" ); document.write( "now find \"sin%28v%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"sin%5E2+%28v%29+%2Bcos%5E2%28v%29=1\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%5E2+%28v%29+%2B%2824%2F25%29%5E2=1\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%5E2+%28v%29+=1-%2824%2F25%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%5E2+%28v%29+=1-576%2F625\"\r
\n" ); document.write( "\n" ); document.write( "\"sin%5E2+%28v%29+=49%2F625\"\r
\n" ); document.write( "\n" ); document.write( "\"sin+%28v%29+=sqrt%2849%2F625%29\"\r
\n" ); document.write( "\n" ); document.write( "\"sin+%28v%29+=7%2F25\" or \"sin+%28v%29+=-7%2F25\"\r
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\n" ); document.write( "\n" ); document.write( " since in Quadrant IV , use \"sin+%28v%29+=-7%2F25\"\r
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\n" ); document.write( "\n" ); document.write( "so we have:\r
\n" ); document.write( "\n" ); document.write( "\"sin+%28u%29+=+-12%2F13\" and \"cos%28u%29=+5%2F13+\"
\n" ); document.write( "\"sin+%28v%29+=-7%2F25\" and\"cos+%28v+%29=+24%2F25\"\r
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\n" ); document.write( "\n" ); document.write( " a)\r
\n" ); document.write( "\n" ); document.write( "\"sin+%28u%2Bv%29+=sin%28u%29+cos%28v%29+%2B+cos%28u%29+sin%28v%29\"......substitute given values\r
\n" ); document.write( "\n" ); document.write( "\"sin+%28u%2Bv%29+=%28-12%2F13+%29+%2824%2F25%29+%2B+%285%2F13+%29+%28-7%2F25%29\"\r
\n" ); document.write( "\n" ); document.write( "\"sin+%28u%2Bv%29+=-288%2F325++-7%2F65\"\r
\n" ); document.write( "\n" ); document.write( "\"sin+%28u%2Bv%29+=-323%2F325\"\r
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\n" ); document.write( "\n" ); document.write( "b)\r
\n" ); document.write( "\n" ); document.write( "\"sin+%28u%29+=+-12%2F13\" and \"cos%28u%29=+5%2F13+\"
\n" ); document.write( "\"sin+%28v%29+=-7%2F25\" and\"cos+%28v+%29=+24%2F25\"\r
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\n" ); document.write( "\n" ); document.write( "\"cos%28v-u%29+=sin%28u%29+sin%28v%29+%2B+cos%28u%29+cos%28v%29\"\r
\n" ); document.write( "\n" ); document.write( "\"cos%28v-u%29+=%28-12%2F13%29+%28-7%2F25%29+%2B+%285%2F13%29+%2824%2F25%29\"\r
\n" ); document.write( "\n" ); document.write( "\"cos%28v-u%29+=84%2F325+%2B+24%2F65\"\r
\n" ); document.write( "\n" ); document.write( "\"cos%28v-u%29+=204%2F325\"\r
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\n" ); document.write( "\n" ); document.write( "c)\r
\n" ); document.write( "\n" ); document.write( "\"sin+%28u%29+=+-12%2F13\" and \"cos%28u%29=+5%2F13+\"
\n" ); document.write( "\"sin+%28v%29+=-7%2F25\" and\"cos+%28v+%29=+24%2F25\"\r
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\n" ); document.write( "\n" ); document.write( "\"tan%28u-v%29=sin%28u-v%29%2Fcos%28u-v%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"tan%28u-v%29=%28-253%2F325%29+%2F+%28204%2F325%29\"\r
\n" ); document.write( "\n" ); document.write( "\"tan%28u-v%29=-253%2F204\"\r
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