document.write( "Question 699419: find the zeroes:\r
\n" ); document.write( "\n" ); document.write( "f(x) = x^4+x^2-20 \n" ); document.write( "

Algebra.Com's Answer #431356 by MathLover1(20850) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"f%28x%29+=+x%5E4%2Bx%5E2-20\"$ ......replace $\"x%5E2\"$ with $\"5x%5E2-4x%5E2\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"f%28x%29+=+x%5E4%2B5x%5E2-4x%5E2-20\"$ ..group\r
\n" ); document.write( "\n" ); document.write( " $\"f%28x%29+=+%28x%5E4%2B5x%5E2%29-%284x%5E2%2B20%29\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"f%28x%29+=+x%5E2%28x%5E2%2B5%29-4%28x%5E2%2B5%29\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"f%28x%29+=+%28x%5E2-4%29++%28x%5E2%2B5%29\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"f%28x%29+=+%28x-2%29+%28x%2B2%29+%28x%5E2%2B5%29\"$ \r
\n" ); document.write( "\n" ); document.write( "solutions:\r
\n" ); document.write( "\n" ); document.write( " $\"+%28x-2%29+%28x%2B2%29+%28x%5E2%2B5%29=0\"$ \r
\n" ); document.write( "\n" ); document.write( "if $\"+x-2=0\"$ ...=>... $\"+x=2\"$ \r
\n" ); document.write( "\n" ); document.write( "if $\"+x%2B2=0\"$ ...=>... $\"+x=-2\"$ \r
\n" ); document.write( "\n" ); document.write( "if $\"+x%5E2%2B5=0\"$ ...=>... $\"+x%5E2=-5\"$ ...=>... $\"+x=sqrt%28-5%29\"$ ...=>... $\"+x=2.24i\"$ or $\"+x=-2.24i\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"+graph%28+600%2C+600%2C+-5%2C+5%2C+-30%2C+10%2C+x%5E4%2Bx%5E2-20%29+\"$ \r
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