document.write( "Question 110923: f(x)=\r
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Algebra.Com's Answer #80903 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"f%28x%29=%28x%5E2-3x-10%29%2F%28x%5E2-6x%2B9%29\" Start with the given function\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-6x%2B9=0\" Set the denominator equal to zero. Remember, dividing by 0 is undefined. So if we find values of x that make the denominator zero, then we must exclude them from the domain.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-3%29%28x-3%29=0\" Factor the left side (note: if you need help with factoring, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "Now set each factor equal to zero:\r
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\n" ); document.write( "\n" ); document.write( "\"x-3=0\" or \"x-3=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=3\" or \"x=3\" Now solve for x in each case\r
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\n" ); document.write( "\n" ); document.write( "Since these two answers are the same, our only solution is \"x=3\"\r
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\n" ); document.write( "\n" ); document.write( "Since \"x=3\" makes the denominator equal to zero, this means we must exclude \"x=3\" from our domain\r
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\n" ); document.write( "\n" ); document.write( "So our domain is: \r
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\n" ); document.write( "\n" ); document.write( "which in plain English reads: x is the set of all real numbers except \"x%3C%3E3\"\r
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\n" ); document.write( "\n" ); document.write( "So our domain looks like this in interval notation\r
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\n" ); document.write( "\n" ); document.write( "note: remember, the parenthesis excludes 3 from the domain\r
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\n" ); document.write( "\n" ); document.write( "To find the x-intercepts, set the entire expression equal to zero\r
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\n" ); document.write( "\n" ); document.write( "\"0=%28x%5E2-3x-10%29%2F%28x%5E2-6x%2B9%29\"\r
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\n" ); document.write( "\n" ); document.write( "So this means the numerator can only equal zero\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-3x-10=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-5%29%28x%2B2%29=0\" Factor the left side (note: if you need help with factoring, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "Now set each factor equal to zero:\r
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\n" ); document.write( "\n" ); document.write( "\"x-5=0\" or \"x%2B2=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=5\" or \"x=-2\" Now solve for x in each case\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are \"x=5\" or \"x=-2\"\r
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\n" ); document.write( "\n" ); document.write( "This means the x intercepts are (-2,0) or (5,0)\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph \"f%28x%29=%28x%5E2-3x-10%29%2F%28x%5E2-6x%2B9%29\", we can see that the x intercepts are (-2,0) or (5,0) and \"x=3\" is not in the domain
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C+%28x%5E2-3x-10%29%2F%28x%5E2-6x%2B9%29%29+\"\r
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\n" ); document.write( "\n" ); document.write( "So this verifies our answer.
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