document.write( "Question 198878: Factor completely x^4+2x^3-3x-6
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Algebra.Com's Answer #149366 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
# 1\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E4%2B2x%5E3-3x-6\" Start with the given expression\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E4%2B2x%5E3%29%2B%28-3x-6%29\" Group like terms\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3%28x%2B2%29-3%28x%2B2%29\" Factor out the GCF \"x%5E3\" out of the first group. Factor out the GCF \"-3\" out of the second group\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E3-3%29%28x%2B2%29\" Since we have the common term \"x%2B2\", we can combine like terms\r
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\n" ); document.write( "\n" ); document.write( "So \"x%5E4%2B2x%5E3-3x-6\" factors to \"%28x%5E3-3%29%28x%2B2%29\"\r
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\n" ); document.write( "\n" ); document.write( "# 2\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E8-1\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E4%29%5E2-1\" Rewrite \"x%5E8\" as \"%28x%5E4%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E4%29%5E2-%281%29%5E2\" Rewrite \"1\" as \"%281%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "Notice how we have a difference of squares \"A%5E2-B%5E2\" where in this case \"A=x%5E4\" and \"B=1\".\r
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\n" ); document.write( "\n" ); document.write( "So let's use the difference of squares formula \"A%5E2-B%5E2=%28A-B%29%28A%2BB%29\" to factor the expression:\r
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\n" ); document.write( "\n" ); document.write( "\"A%5E2-B%5E2=%28A-B%29%28A%2BB%29\" Start with the difference of squares formula.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E4%29%5E2-%281%29%5E2=%28x%5E4-1%29%28x%5E4%2B1%29\" Plug in \"A=x%5E4\" and \"B=1\".\r
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\n" ); document.write( "\n" ); document.write( "So this shows us that \"x%5E8-1\" factors to \"%28x%5E4-1%29%28x%5E4%2B1%29\".\r
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\n" ); document.write( "\n" ); document.write( "In other words \"x%5E8-1=%28x%5E4-1%29%28x%5E4%2B1%29\".\r
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\n" ); document.write( "\n" ); document.write( "Now let's factor \"x%5E4-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E4-1\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%29%5E2-1\" Rewrite \"x%5E4\" as \"%28x%5E2%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%29%5E2-%281%29%5E2\" Rewrite \"1\" as \"%281%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "Notice how we have a difference of squares \"A%5E2-B%5E2\" where in this case \"A=x%5E2\" and \"B=1\".\r
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\n" ); document.write( "\n" ); document.write( "So let's use the difference of squares formula \"A%5E2-B%5E2=%28A-B%29%28A%2BB%29\" to factor the expression:\r
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\n" ); document.write( "\n" ); document.write( "\"A%5E2-B%5E2=%28A-B%29%28A%2BB%29\" Start with the difference of squares formula.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%29%5E2-%281%29%5E2=%28x%5E2-1%29%28x%5E2%2B1%29\" Plug in \"A=x%5E2\" and \"B=1\".\r
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\n" ); document.write( "\n" ); document.write( "So this shows us that \"x%5E4-1\" factors to \"%28x%5E2-1%29%28x%5E2%2B1%29\".\r
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\n" ); document.write( "\n" ); document.write( "In other words \"x%5E4-1=%28x%5E2-1%29%28x%5E2%2B1%29\".\r
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\n" ); document.write( "\n" ); document.write( "So this means that \"%28x%5E4-1%29%28x%5E4%2B1%29\" factors to \"%28x%5E2-1%29%28x%5E2%2B1%29%28x%5E4%2B1%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's factor \"x%5E2-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-1\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%29%5E2-1\" Rewrite \"x%5E2\" as \"%28x%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%29%5E2-%281%29%5E2\" Rewrite \"1\" as \"%281%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "Notice how we have a difference of squares \"A%5E2-B%5E2\" where in this case \"A=x\" and \"B=1\".\r
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\n" ); document.write( "\n" ); document.write( "So let's use the difference of squares formula \"A%5E2-B%5E2=%28A-B%29%28A%2BB%29\" to factor the expression:\r
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\n" ); document.write( "\n" ); document.write( "\"A%5E2-B%5E2=%28A-B%29%28A%2BB%29\" Start with the difference of squares formula.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%29%5E2-%281%29%5E2=%28x-1%29%28x%2B1%29\" Plug in \"A=x\" and \"B=1\".\r
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\n" ); document.write( "\n" ); document.write( "So this shows us that \"x%5E2-1\" factors to \"%28x-1%29%28x%2B1%29\".\r
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\n" ); document.write( "\n" ); document.write( "In other words \"x%5E2-1=%28x-1%29%28x%2B1%29\".\r
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\n" ); document.write( "\n" ); document.write( "So this means that \"%28x%5E2-1%29%28x%5E2%2B1%29%28x%5E4%2B1%29\" factors to \"%28x-1%29%28x%2B1%29%28x%5E2%2B1%29%28x%5E4%2B1%29\"\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So \"x%5E8-1\" completely factors to \"%28x-1%29%28x%2B1%29%28x%5E2%2B1%29%28x%5E4%2B1%29\"
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