document.write( "Question 134056: Graph (x+3) (x-2)^2=0 (use maxs, mins, x and y intercepts) \n" ); document.write( "
Algebra.Com's Answer #98085 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
\"%28x%2B3%29+%28x-2%29%5E2=0\" doesn't actually have a graph other than the three values (-3, 2, and 2) on the number line that satisfy the equation. You can, however, graph \"f%28x%29=%28x%2B3%29%28x-2%29%5E2\", and I suspect that is what you really meant. (I sincerely hope your instructor didn't pose the question that way. If s/he did, go get your money back)\r
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\n" ); document.write( "\n" ); document.write( "Zeros, or x-intercepts at -3, 2, and 2 (we should have an extrema at 2)\r
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\n" ); document.write( "\n" ); document.write( "Expand:
\n" ); document.write( "\"f%28x%29=x%5E3-x%5E2-8x%2B12\"\r
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\n" ); document.write( "\n" ); document.write( "Extreme points where f'(x) = 0, so:\r
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\n" ); document.write( "\n" ); document.write( "f'(x) = \"3x%5E2-2x-8\". Set the first derivative equal to zero:\r
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\n" ); document.write( "\n" ); document.write( "\"3x%5E2-2x-8=0\"
\n" ); document.write( "\"%283x%2B4%29%28x-2%29=0\", hence critical points are at (\"-4%2F3\",\"f%28-4%2F3%29\") and (\"2\",\"f%282%29\").\r
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\n" ); document.write( "\n" ); document.write( "We know that \"f%282%29=0\", so we have a critical point at (2,0).\r
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\n" ); document.write( "\n" ); document.write( "\"f%28-4%2F3%29=%28%28-4%2F3%29%2B3%29%28%28-4%2F3%29-2%29%5E2\"
\n" ); document.write( "\"f%28-4%2F3%29=%285%2F3%29%28-10%2F3%29%5E2\"
\n" ); document.write( "\"f%28-4%2F3%29=%285%2F3%29%28100%2F9%29\"
\n" ); document.write( "\"f%28-4%2F3%29=%28500%2F27%29\"\r
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\n" ); document.write( "\n" ); document.write( "And we have an extreme point at \"-4%2F3\",\"500%2F27\")\r
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\n" ); document.write( "\n" ); document.write( "f\"(x)=\"6x-2\"
\n" ); document.write( "f\"(2)=\"8-2=6%3E0\" => (2,f(2)) is a local minimum
\n" ); document.write( "f\"(-4/3)=\"6%28-4%2F3%29-2=-8-2=-10%3C0\" => (\"-4%2F3\",\"f%28-4%2F3%29\") is a local maximum\r
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\n" ); document.write( "\n" ); document.write( "The y-intercept is found by evaluating f(0):
\n" ); document.write( "\"f%280%29=0%5E3-0%5E2-80%2B12=12\" hence the y-intercept is (0,12)\r
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\n" ); document.write( "\n" ); document.write( "Using this information, we can make a rough sketch of the graph:\r
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