document.write( "Question 129111: 2. Solve by graphical means:
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\n" ); document.write( " x^3 – x^2 – 4x + 4 < 0
\n" ); document.write( "(Hint: factor by grouping) Label the vertex and axis.
\n" ); document.write( "Denote the left-hand side by f(x). Factor to find the x intercepts, and sketch the graph with the aid of a few additional points.
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Algebra.Com's Answer #94379 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Let's factor \"x%5E3-x%5E2-4x%2B4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3-x%5E2-4x%2B4\" Start with the given expression\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E3-x%5E2%29%2B%28-4x%2B4%29\" Group like terms\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%28x-1%29-4%28x-1%29\" Factor out the GCF \"x%5E2\" out of the first group. Factor out the GCF \"-4\" out of the second group\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2-4%29%28x-1%29\" Since we have the common term \"x-1\", we can combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B2%29%28x-2%29%28x-1%29\" Now factor \"x%5E2-4\" to get \"%28x%2B2%29%28x-2%29\"\r
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\n" ); document.write( "\n" ); document.write( "So \"x%5E3-x%5E2-4x%2B4\" factors to \"%28x%2B2%29%28x-2%29%28x-1%29\"\r
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\n" ); document.write( "\n" ); document.write( "Notice if we solve \"%28x%2B2%29%28x-2%29%28x-1%29=0\" we find the zeros \"x=-2\", \"x=1\" and \"x=2\"\r
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\n" ); document.write( "\n" ); document.write( "In order to solve \"x%5E3-x%5E2-4x%2B4%3C0\" we need to test some points. So let's pick a point that is less than \"x=-2\"\r
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\n" ); document.write( "\n" ); document.write( "So let's test \"x=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3-x%5E2-4x%2B4%3C0\" Start with the given inequality\r
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\n" ); document.write( "\n" ); document.write( "\"%28-3%29%5E3-%28-3%29%5E2-4%28-3%29%2B4%3C0\" Plug in \"x=-3\" \r
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\n" ); document.write( "\n" ); document.write( "\"-20%3C0\" Simplify. Since this inequality is true, any value that is less than \"x=-2\" will satisfy the inequality.\r
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\n" ); document.write( "\n" ); document.write( "Now let's test a value that is in between \"x=-2\" and \"x=1\"\r
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\n" ); document.write( "\n" ); document.write( "So let's test \"x=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3-x%5E2-4x%2B4%3C0\" Start with the given inequality\r
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\n" ); document.write( "\n" ); document.write( "\"%280%29%5E3-%280%29%5E2-4%280%29%2B4%3C0\" Plug in \"x=0\" \r
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\n" ); document.write( "\n" ); document.write( "\"4%3C0\" Simplify. Since this inequality is not true, this means that the interval [-2,1] is not in the solution set.\r
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\n" ); document.write( "\n" ); document.write( "Now let's test a value that is in between \"x=1\" and \"x=2\"\r
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\n" ); document.write( "\n" ); document.write( "So let's test \"x=1.5\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3-x%5E2-4x%2B4%3C0\" Start with the given inequality\r
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\n" ); document.write( "\n" ); document.write( "\"%281.5%29%5E3-%281.5%29%5E2-4%281.5%29%2B4%3C0\" Plug in \"x=1.5\" \r
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\n" ); document.write( "\n" ); document.write( "\"-0.875%3C0\" Simplify. Since this inequality is true, any value that is in between x=1 and x=2 will satisfy the inequality.\r
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\n" ); document.write( "\n" ); document.write( "Now let's test a value that is greater than \"x=2\"\r
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\n" ); document.write( "\n" ); document.write( "So let's test \"x=3\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3-x%5E2-4x%2B4%3C0\" Start with the given inequality\r
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\n" ); document.write( "\n" ); document.write( "\"%283%29%5E3-%283%29%5E2-4%283%29%2B4%3C0\" Plug in \"x=3\" \r
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\n" ); document.write( "\n" ); document.write( "\"10%3C0\" Simplify. Since this inequality is not true, this means that any value greater than x=2 will not satisfy the inequality\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the solution set is\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph \"y=x%5E3-x%5E2-4x%2B4\", we can visually verify our answer.\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C+x%5E3-x%5E2-4x%2B4%29+\"
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