document.write( "Question 156274: Find f(15) for f (x) = x^2-4/8-x^3 \n" ); document.write( "

Algebra.Com's Answer #115119 by orca(409) $\"\"$ $\"About$

You can put this solution on YOUR website!
Note that the expression $\"%28x%5E2-4%29%2F%288-x%5E3%29\"$ can be simplified.
\n" ); document.write( " $\"%28x%5E2-4%29%2F%288-x%5E3%29\"$
\n" ); document.write( "= $\"%28x%5E2-4%29%2F%28-%28x%5E3-8%29%29\"$ (As 8 - x^3 = -(x^3 - 8))
\n" ); document.write( "= $\"-%28x%5E2-4%29%2F%28x%5E3-8%29\"$
\n" ); document.write( "= $\"-%28x%5E2-2%5E2%29%2F%28x%5E3-2%5E3%29\"$
\n" ); document.write( "= $\"-%28%28x%2B2%29%28x-2%29%29%2F%28%28x-2%29%28x%5E2%2B2x%2B4%29%29\"$
\n" ); document.write( "= $\"-%28%28x%2B2%29cross%28%28x-2%29%29%29%2F%28cross%28%28x-2%29%29%28x%5E2%2B2x%2B4%29%29\"$
\n" ); document.write( "= $\"-%28x%2B2%29%2F%28x%5E2%2B2x%2B4%29\"$
\n" ); document.write( "Now substitute x = 15 into the above expression to find f(15).
\n" ); document.write( " $\"f%2815%29=+-%2815%2B2%29%2F%2815%5E2%2B2%2A15%2B4%29\"$
\n" ); document.write( "= $\"-17%2F259\"$
\n" ); document.write( " \n" ); document.write( "

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