document.write( "Question 977183: Hello!
\n" ); document.write( "I need help solving this.\r
\n" ); document.write( "\n" ); document.write( "f(x)= x^2-3x-18/(x^2-4)\r
\n" ); document.write( "\n" ); document.write( "What is the domain of the function, x-intercepts, y-intercept, vertical asymptote and horizontal asymptote and graph.
\n" ); document.write( "Please explain each step.
\n" ); document.write( "Thank you
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Algebra.Com's Answer #598717 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\"f%28x%29=%28x%5E2-3x-18%29%2F%28x%5E2-4%29+\"
\n" ); document.write( "\"f%28x%29=%28x%5E2-3x%2B6x-18%29%2F%28%28x-2%29+%28x%2B2%29%29\"
\n" ); document.write( "\"f%28x%29=%28%28x%5E2-3x%29%2B%286x-18%29%29%2F%28%28x-2%29+%28x%2B2%29%29\"
\n" ); document.write( "\"f%28x%29=%28x%28x-3%29%2B6%28x-3%29%29%2F%28%28x-2%29+%28x%2B2%29%29\"
\n" ); document.write( " \"f%28x%29=%28%28x%2B3%29+%28x-6%29%29%2F%28%28x-2%29+%28x%2B2%29%29\"\r
\n" ); document.write( "\n" ); document.write( "since denominator cannot be equal to zero, domain will be all values of \"x\" element of \"R\" excluding values of \"x\" that make denominator equal to zero and they are\r
\n" ); document.write( "\n" ); document.write( "\"%28x-2%29+%28x%2B2%29=0\"\r
\n" ); document.write( "\n" ); document.write( "if \"x-2=0\"=>\"x=2\"
\n" ); document.write( "if \"x%2B2=0\" =>\"x=-2\"\r
\n" ); document.write( "\n" ); document.write( "so, the domain is \r
\n" ); document.write( "\n" ); document.write( "{ \"x\" element \"R\" :\"+x%3C%3E-2\" and \"x%3C%3E2\" }\r
\n" ); document.write( "\n" ); document.write( "x-intercepts:\r
\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29+%28x-6%29=0\"
\n" ); document.write( "if \"x%2B3=0\" =>\"x=-3\"
\n" ); document.write( "if \"x-6=0\"=>\"x=6\"\r
\n" ); document.write( "\n" ); document.write( "x-intercepts are at (\"-3\",\"+0\") and (\"6\",\"+0\")\r
\n" ); document.write( "\n" ); document.write( "y-intercepts:if \"x=0\"
\n" ); document.write( "\"f%280%29=%28%28x%2B3%29+%28x-6%29%29%2F%28%28x-2%29+%28x%2B2%29%29\"
\n" ); document.write( "\"f%280%29=%28%280%2B3%29+%280-6%29%29%2F%28%280-2%29+%280%2B2%29%29\"
\n" ); document.write( "\"f%280%29=%28%283%29+%28-6%29%29%2F%28%28-2%29+%282%29%29\"
\n" ); document.write( "\"f%280%29=-18%2F%28-4%29\"
\n" ); document.write( "\"f%280%29=9%2F2\"\r
\n" ); document.write( "\n" ); document.write( "y-intercept is at (\"0\", \"9%2F2\")\r
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\n" ); document.write( "\n" ); document.write( "asymptotes:
\n" ); document.write( "since x-intercepts at \"x=2\" and \"x=2\", the vertical asymptotes are at \"x=2\" and \"x=-2\"\r
\n" ); document.write( "\n" ); document.write( "Other asymptotes, if any, occur for large positive or negative values of x's (way off to the right or left on the graph). To find them you have to analyze the function for high values. One way to do this is to divide the numerator and denominator by the highest power of x in the function. For this equation, that would be \"x%5E2\":\r
\n" ); document.write( "\n" ); document.write( "what happens to y for large \"x\"'s?
\n" ); document.write( "When \"x\" has very large values, all those little fractions will have very large denominators. And fractions with very large denominators are very small numbers. In fact, the larger \"x\" gets the closer the fraction as a whole gets to \"zero\"! So if we replace replace all those little fractions with an \"x\" in the denominator with zeros we can see the value that y approaches for large \"x\"'s:\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=%28x%5E2-3x-18%29%2F%28x%5E2-4%29+\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=%28x%5E2%2Fx%5E2-3x%2Fx%5E2-18%2Fx%5E2%29%2F%28x%5E2%2Fx%5E2-4%2Fx%5E2%29+\"\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=%281-3%2Fx-18%2Fx%5E2%29%2F%281-4%2Fx%5E2%29+\"
\n" ); document.write( "\"f%28x%29=%281-0-0%29%2F%281-0%29+\"
\n" ); document.write( "\"f%28x%29=1%2F1\"
\n" ); document.write( "\"f%28x%29=1+\"\r
\n" ); document.write( "\n" ); document.write( "So \"y+=+1\" is the horizontal asymptote.\r
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