document.write( "Question 128507: Find the domain and range of the following\r
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Algebra.Com's Answer #94022 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( "\"y=%287%29%2F%28x%2B9%29\" Start with the given function\r
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\n" ); document.write( "\n" ); document.write( "\"x%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( "\"x=0-9\"Subtract 9 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x=-9\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "Since \"x=-9\" makes the denominator equal to zero, this means we must exclude \"x=-9\" 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%3E-9\"\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 -9 from the domain\r
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\n" ); document.write( "\n" ); document.write( "Now to find the range, simply graph the function to get\r
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\n" ); document.write( "\n" ); document.write( "note: ignore the vertical lines, they are not part of the graph and are asymptotes\r
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\n" ); document.write( "\n" ); document.write( "Looking at the graph, we can see that y can be any number except 0. So \"y%3C%3E0\". \r
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\n" ); document.write( "\n" ); document.write( "So our range is: \r
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\n" ); document.write( "\n" ); document.write( "which in plain English reads: y is the set of all real numbers except \"y%3C%3E0\"\r
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\n" ); document.write( "\n" ); document.write( "So our range looks like this in interval notation\r
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\n" ); document.write( "\n" ); document.write( "note: remember, the parenthesis excludes 0 from the range\r
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\r
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\n" ); document.write( "\n" ); document.write( "e)\r
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\n" ); document.write( "\n" ); document.write( "\"y=%283%29%2F%28x%5E2-4%29\" Start with the given function\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-4=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-2%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-2=0\" or \"x%2B2=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=2\" 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=2\" or \"x=-2\"\r
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\n" ); document.write( "\n" ); document.write( "Since \"x=-2\" and \"x=2\" make the denominator equal to zero, this means we must exclude \"x=-2\" and \"x=2\" 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%3E-2\" or \"x%3C%3E2\"\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 -2 and 2 from the domain\r
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\n" ); document.write( "\n" ); document.write( "Now to find the range, simply graph the function to get\r
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\n" ); document.write( "\n" ); document.write( "note: ignore the vertical lines, they are not part of the graph and are asymptotes\r
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\n" ); document.write( "\n" ); document.write( "\"graph%28500%2C500%2C-15%2C5%2C-10%2C10%2C%283%29%2F%28x%5E2-4%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Looking at the graph, we can see that y can be any number except 0. So \"y%3C%3E0\". \r
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\n" ); document.write( "\n" ); document.write( "So our range is: \r
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\n" ); document.write( "\n" ); document.write( "which in plain English reads: y is the set of all real numbers except \"y%3C%3E0\"\r
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\n" ); document.write( "\n" ); document.write( "So our range looks like this in interval notation\r
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