document.write( "Question 1163852: Find the exact value of the trigonometric function below given that sin u = -7/25 and cos v = -4/5. (Both u and v are in Quadrant III).\r
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Algebra.Com's Answer #788074 by Tatiana_Stebko(1539) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"cos%28u-v%29=cos+u%2Acosv%2Bsinu%2Asinv\"$
\n" ); document.write( " $\"%28sin++u%29%5E2%2B%28cos+u%29%5E2=1\"$
\n" ); document.write( " $\"%28-7%2F25%29%5E2%2B%28cos+u%29%5E2=1\"$
\n" ); document.write( " $\"49%2F625%2B%28cos+u%29%5E2=1\"$
\n" ); document.write( " $\"%28cos+u%29%5E2=1-49%2F625\"$
\n" ); document.write( " $\"%28cos+u%29%5E2=576%2F625\"$
\n" ); document.write( " $\"u\"$ is in Quadrant III, therefore $\"cos+u=-sqrt%28576%2F625%29\"$
\n" ); document.write( " $\"cos+u=-24%2F25\"$
\n" ); document.write( " $\"%28sin++v%29%5E2%2B%28cos+v%29%5E2=1\"$
\n" ); document.write( " $\"%28sin++v%29%5E2%2B%28-4%2F5%29%5E2=1\"$
\n" ); document.write( " $\"%28sin++v%29%5E2%2B16%2F25=1\"$
\n" ); document.write( " $\"%28sin+v%29%5E2=1-16%2F25\"$
\n" ); document.write( " $\"%28sin+v%29%5E2=9%2F25\"$
\n" ); document.write( " $\"v\"$ is in Quadrant III, therefore $\"sin+v=-sqrt%289%2F25%29\"$
\n" ); document.write( " $\"sin+v=-3%2F5\"$
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