document.write( "Question 812135:
\n" ); document.write( " Find the roots of the polynomial equation: x^3 – 3x^2 + 9x – 7 = 0 \n" ); document.write( "
Algebra.Com's Answer #492930 by tommyt3rd(5050)\"\" \"About 
You can put this solution on YOUR website!
x^3–3x^2+9x–7=
\n" ); document.write( "x(x^2-2x+1)-(x^2-8x+7)=
\n" ); document.write( "x(x-1)^2-(x-1)(x-7)=
\n" ); document.write( "(x-1)[x(x-1)-(x-7)]=
\n" ); document.write( "(x-1)(x^2-x-x+7)=
\n" ); document.write( "(x-1)(x^2-2x+7)\r
\n" ); document.write( "\n" ); document.write( "the last two are irrational so...\r
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B-2x%2B7+=+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=%28-2%29%5E2-4%2A1%2A7=-24\".
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\n" ); document.write( " The discriminant -24 is less than zero. That means that there are no solutions among real numbers.

\n" ); document.write( " If you are a student of advanced school algebra and are aware about imaginary numbers, read on.

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\n" ); document.write( " In the field of imaginary numbers, the square root of -24 is + or - \"sqrt%28+24%29+=+4.89897948556636\".
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\n" ); document.write( " The solution is
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\n" ); document.write( " Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-2%2Ax%2B7+%29\"
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