document.write( "Question 250686: could you PLEASE help me solve this trig identity.
\n" ); document.write( "(6sinx)-(5cosx)-(2)=0 and the range is (0,2pi)
\n" ); document.write( "im pretty sure i have to factor it but i cant seem to figure out how to do.
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Algebra.Com's Answer #182643 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
could you PLEASE help me solve this trig identity.
\n" ); document.write( "(6sinx)-(5cosx)-(2)=0
\n" ); document.write( "That's not an identity, it's an equation in x.
\n" ); document.write( "6sin - 5*sqrt(1-sin^2) - 2 = 0
\n" ); document.write( "6sin -2 = 5sqrt(1-sin^2)
\n" ); document.write( "36sin^2 - 24sin + 4 = 25 - 25sin^2
\n" ); document.write( "61sin^2 - 24sin - 21 = 0
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Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"61x%5E2%2B-24x%2B-21+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-24%29%5E2-4%2A61%2A-21=5700\".
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\n" ); document.write( " Discriminant d=5700 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--24%2B-sqrt%28+5700+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-24%29%2Bsqrt%28+5700+%29%29%2F2%5C61+=+0.815560199612356\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-24%29-sqrt%28+5700+%29%29%2F2%5C61+=+-0.422117576661537\"
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\n" ); document.write( " Quadratic expression \"61x%5E2%2B-24x%2B-21\" can be factored:
\n" ); document.write( " \"61x%5E2%2B-24x%2B-21+=+%28x-0.815560199612356%29%2A%28x--0.422117576661537%29\"
\n" ); document.write( " Again, the answer is: 0.815560199612356, -0.422117576661537.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+61%2Ax%5E2%2B-24%2Ax%2B-21+%29\"

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\n" ); document.write( "The solver uses x, it's actually sin(x)
\n" ); document.write( "sin(x) = 0.8155602
\n" ); document.write( "sin(x) = -0.4221176
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\n" ); document.write( "Use a calculator to find x
\n" ); document.write( "Email me via the thank you note to check your work, or for assistance.\r
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