document.write( "Question 180459: x^6-3x^3-18=0 \n" ); document.write( "

Algebra.Com's Answer #135396 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
Use a subsitution to transform this equation to a quadratic equation.
\n" ); document.write( "Let $\"z=x%5E3\"$ , then
\n" ); document.write( " $\"x%5E6-3x%5E3-18=z%5E2-3z-18=0\"$
\n" ); document.write( " $\"%28z-6%29%28z%2B3%29=0\"$
\n" ); document.write( "First solution:
\n" ); document.write( " $\"z-6=0\"$
\n" ); document.write( " $\"z=6\"$
\n" ); document.write( " $\"x%5E3=6\"$
\n" ); document.write( " $\"x=6%5E%281%2F3%29\"$
\n" ); document.write( "Second solution:
\n" ); document.write( " $\"z%2B3=0\"$
\n" ); document.write( " $\"z=-3\"$
\n" ); document.write( " $\"x%5E3=-3\"$
\n" ); document.write( " $\"x=-3%5E%281%2F3%29\"$
\n" ); document.write( " \n" ); document.write( "

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