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<!DOCTYPE document PUBLIC "-//CNX//DTD CNXML 0.5 plus MathML//EN" "http://cnx.rice.edu/cnxml/0.5/DTD/cnxml_mathml.dtd">
<document xmlns="http://cnx.rice.edu/cnxml" xmlns:md="http://cnx.rice.edu/mdml/0.4" xmlns:bib="http://bibtexml.sf.net/" xmlns:m="http://www.w3.org/1998/Math/MathML" id="new">
	<name>Horizontal Asymptotes</name>
	<metadata>
  <md:version>1.8</md:version>
  <md:created>2006/03/27 16:50:26 US/Central</md:created>
  <md:revised>2007/04/08 17:41:38.976 GMT-5</md:revised>
  <md:authorlist>
      <md:author id="pradnyab89">
      <md:firstname>Pradnya</md:firstname>
      <md:othername>Vinay</md:othername>
      <md:surname>Bhawalkar</md:surname>
      <md:email>pradnyab89@gmail.com</md:email>
    </md:author>
      <md:author id="kjohnston">
      <md:firstname>Kim</md:firstname>
      <md:othername>Dodge</md:othername>
      <md:surname>Johnston</md:surname>
      <md:email>kim.johnston@fortbend.k12.tx.us</md:email>
    </md:author>
  </md:authorlist>

  <md:maintainerlist>
    <md:maintainer id="pradnyab89">
      <md:firstname>Pradnya</md:firstname>
      <md:othername>Vinay</md:othername>
      <md:surname>Bhawalkar</md:surname>
      <md:email>pradnyab89@gmail.com</md:email>
    </md:maintainer>
  </md:maintainerlist>
  
  <md:keywordlist>
    <md:keyword>Asymptote</md:keyword>
    <md:keyword>Horizonatl Asymptote</md:keyword>
    <md:keyword>Horizontal</md:keyword>
    <md:keyword>Rational Function</md:keyword>
  </md:keywordlist>

  <md:abstract>Finding horizontal asymptotes of rational functions</md:abstract>
</metadata>
	<content>
		<para id="delete_me"><term>Horizontal asymptotes</term> are horizontal lines the graph approaches. </para><para id="element-804">Horizontal Asymptotes CAN be crossed.</para><para id="element-438">To find horizontal asymptotes:</para><list id="element-900" type="bulleted"><item>If the degree (the largest exponent) of the denominator is <emphasis>bigger than </emphasis> the degree of the numerator, the horizontal asymptote is the x-axis (y = 0). </item>
			<item>If the degree of the numerator is <emphasis>bigger than</emphasis> the denominator, there is no horizontal asymptote.</item>
			<item>If the degrees of the numerator and denominator are the <emphasis>same</emphasis>, the horizontal asymptote equals the leading coefficient (the coefficient of the largest exponent) of the numerator divided by the leading coefficient of the denominator</item>
		</list><para id="element-304">One way to remember this is the following pnemonic device: BOBO BOTN EATS DC</para><list id="element-16" type="bulleted"><item>BOBO - Bigger on bottom, y=0</item>
			<item>BOTN - Bigger on top, none </item>
			<item>EATS DC - Exponents are the same, divide coefficients</item></list><para id="element-571">Find the Horizontal Asymptotes of the following:</para><exercise id="element-455"><problem>
				<para id="element-480">
					<m:math>
						<m:apply><m:eq/>
							<m:apply>
								<m:fn><m:ci>f</m:ci></m:fn>
								<m:ci>x</m:ci>
							</m:apply>
							<m:apply><m:divide/>
								<m:apply><m:times/>
									<m:cn>4</m:cn>
									<m:ci>x</m:ci>
								</m:apply>
								<m:apply><m:minus/>
									<m:ci>x</m:ci>
									<m:cn>3</m:cn>
								</m:apply>
							</m:apply>
						</m:apply>
					</m:math>
				</para>
			</problem>
			<solution>
				<para id="element-946"><m:math>
						<m:apply><m:eq/>
							<m:ci>y</m:ci>
							<m:cn>4</m:cn>
						</m:apply>
					</m:math>
 since the degrees are the same, divide the leading coefficients of the numerator and denominator = 
<m:math><m:apply><m:eq/>
							<m:apply><m:divide/>
								<m:cn>4</m:cn>
								<m:cn>1</m:cn>
							</m:apply>
							<m:cn>4</m:cn>
						</m:apply>
					</m:math>
				</para></solution>
		</exercise><exercise id="element-960"><problem>
				<para id="element-892">
					<m:math>
						<m:apply><m:eq/>
							<m:apply>
								<m:fn><m:ci>g</m:ci></m:fn>
								<m:ci>x</m:ci>
							</m:apply>
							<m:apply><m:divide/>
								<m:apply><m:times/>
									<m:cn>5</m:cn>
									<m:apply><m:power/>
										<m:ci>x</m:ci>
										<m:cn>2</m:cn>
									</m:apply>
								</m:apply>
								<m:apply><m:plus/>
									<m:cn>3</m:cn>
									<m:ci>x</m:ci>
								</m:apply>
							</m:apply>
						</m:apply>
					</m:math>
				</para>
			</problem>
			<solution>
				<para id="element-833">None since the degree of the numerator is greater than the degree of the denominator.</para>
			</solution>
		</exercise><exercise id="element-890"><problem>
				<para id="element-915">
					<m:math>
						<m:apply><m:eq/>
							<m:apply>
								<m:fn><m:ci>h</m:ci></m:fn>
								<m:ci>x</m:ci>
							</m:apply>
							<m:apply><m:divide/>
								<m:apply><m:times/>
									<m:cn>-4</m:cn>
									<m:apply><m:power/>
										<m:ci>x</m:ci>
										<m:cn>2</m:cn>
									</m:apply>
								</m:apply>
								<m:apply><m:times/>
									<m:apply><m:minus/>
										<m:ci>x</m:ci>
										<m:cn>2</m:cn>
									</m:apply>
									<m:apply><m:plus/>
										<m:ci>x</m:ci>
										<m:cn>4</m:cn>
									</m:apply>
								</m:apply>
							</m:apply>
						</m:apply>
					</m:math>
				</para>
			</problem>
			<solution>
				<para id="element-95"><m:math>
						<m:apply><m:eq/>
							<m:ci>y</m:ci>
							<m:cn>-4</m:cn>
						</m:apply>
					</m:math></para>
			</solution>
		</exercise><exercise id="element-912"><problem>
				<para id="element-650">
					<m:math>
						<m:apply><m:eq/>
							<m:apply>
								<m:fn><m:ci>g</m:ci></m:fn>
								<m:ci>x</m:ci>
							</m:apply>
							<m:apply><m:divide/>
								<m:cn>6</m:cn>
								<m:apply><m:times/>
									<m:apply><m:plus/>
										<m:ci>x</m:ci>
										<m:cn>3</m:cn>
									</m:apply>
									<m:apply><m:minus/>
										<m:cn>4</m:cn>
										<m:ci>x</m:ci>
									</m:apply>
								</m:apply>
							</m:apply>
						</m:apply>
					</m:math>
				</para>
			</problem>
			<solution>
				<para id="element-100"><m:math>
						<m:apply><m:eq/>
							<m:ci>y</m:ci>
							<m:cn>0</m:cn>
						</m:apply>
					</m:math></para>
			</solution>
		</exercise><exercise id="element-353"><problem>
				<para id="element-260"><m:math>
						<m:apply><m:eq/>
							<m:apply>
								<m:fn><m:ci>f</m:ci></m:fn>
								<m:ci>x</m:ci>
							</m:apply>
							<m:apply><m:divide/>
								<m:apply><m:times/>
									<m:apply><m:times/>
										<m:cn>3</m:cn>
										<m:ci>x</m:ci>
									</m:apply>
									<m:apply><m:minus/>
										<m:ci>x</m:ci>
										<m:cn>1</m:cn>
									</m:apply>
								</m:apply>
								<m:apply><m:minus/>
									<m:apply><m:minus/>
										<m:apply><m:times/>
											<m:cn>2</m:cn>
											<m:apply><m:power/>
												<m:ci>x</m:ci>
												<m:cn>2</m:cn>
											</m:apply>
										</m:apply>
										<m:apply><m:times/>
											<m:cn>5</m:cn>
											<m:ci>x</m:ci>
										</m:apply>
									</m:apply>
									<m:cn>3</m:cn>
								</m:apply>
							</m:apply>
						</m:apply>
					</m:math></para>
			</problem>
			<solution>
				<para id="element-609"><m:math>
						<m:apply><m:eq/>
							<m:ci>y</m:ci>
							<m:apply><m:divide/><m:cn>3</m:cn><m:cn>2</m:cn></m:apply>
						</m:apply>
					</m:math>
				</para>
			</solution>
		</exercise><exercise id="element-684"><problem>
				<para id="element-24">
					<m:math>
						<m:apply><m:eq/>
							<m:apply>
								<m:fn><m:ci>q</m:ci></m:fn>
								<m:ci>x</m:ci>
							</m:apply>
							<m:apply><m:divide/>
								<m:apply><m:times/>
									<m:apply><m:minus/>
										<m:ci>x</m:ci>
									</m:apply>
									<m:apply><m:minus/>
										<m:cn>1</m:cn>
										<m:ci>x</m:ci>
									</m:apply>
								</m:apply>
								<m:apply><m:minus/>
									<m:apply><m:plus/>
										<m:apply><m:times/>
											<m:cn>3</m:cn>
											<m:apply><m:power/>
												<m:ci>x</m:ci>
												<m:cn>2</m:cn>
											</m:apply>
										</m:apply>
										<m:apply><m:times/>
											<m:cn>5</m:cn>
											<m:ci>x</m:ci>
										</m:apply>
									</m:apply>
									<m:cn>2</m:cn>
								</m:apply>
							</m:apply>
						</m:apply>
					</m:math>
				</para>
			</problem>
			<solution>
				<para id="element-209"><m:math>
						<m:apply><m:eq/>
							<m:ci>y</m:ci>
							<m:apply><m:divide/><m:cn>1</m:cn><m:cn>3</m:cn></m:apply>
						</m:apply>
					</m:math></para>
			</solution>
		</exercise><exercise id="element-570"><problem>
				<para id="element-422">
					<m:math>
						<m:apply><m:eq/>
							<m:apply>
								<m:fn><m:ci>r</m:ci></m:fn>
								<m:ci>x</m:ci>
							</m:apply>
							<m:apply><m:divide/>
								<m:ci>x</m:ci>
								<m:apply><m:power/>
									<m:apply><m:minus/>
										<m:ci>x</m:ci>
										<m:cn>8</m:cn>
									</m:apply>
									<m:cn>2</m:cn>
								</m:apply>
							</m:apply>
						</m:apply>
					</m:math>
				</para>
			</problem>
			<solution>
				<para id="element-216"><m:math>
						<m:apply><m:eq/>
							<m:ci>y</m:ci>
							<m:cn>0</m:cn>
						</m:apply>
					</m:math></para>
			</solution>
		</exercise><exercise id="element-355"><problem>
				<para id="element-451">
					<m:math>
						<m:apply><m:eq/>
							<m:apply>
								<m:fn><m:ci>r</m:ci></m:fn>
								<m:ci>x</m:ci>
							</m:apply>
							<m:apply><m:divide/>
								<m:ci>x</m:ci>
								<m:apply><m:minus/>
									<m:apply><m:power/>
										<m:ci>x</m:ci>
										<m:cn>4</m:cn>
									</m:apply>
									<m:cn>1</m:cn>
								</m:apply>
							</m:apply>
						</m:apply>
					</m:math>
				</para>
			</problem>
			<solution>
				<para id="element-412">y = 0</para></solution>
		</exercise><exercise id="element-193"><problem>
				<para id="element-83">
					<m:math>
						<m:apply><m:eq/>
							<m:apply>
								<m:fn><m:ci>g</m:ci></m:fn>
								<m:ci>x</m:ci>
							</m:apply>
							<m:apply><m:divide/>
								<m:apply><m:minus/>
									<m:ci>x</m:ci>
									<m:cn>3</m:cn>
								</m:apply>
								<m:apply><m:plus/>
									<m:apply><m:power/>
										<m:ci>x</m:ci>
										<m:cn>2</m:cn>
									</m:apply>
									<m:cn>1</m:cn>
								</m:apply>
							</m:apply>
						</m:apply>
					</m:math>
				</para>
			</problem>
			<solution>
				<para id="element-161"><m:math>
						<m:apply><m:eq/>
							<m:ci>y</m:ci>
							<m:cn>0</m:cn>
						</m:apply>
					</m:math>
				</para>
			</solution>
		</exercise><exercise id="element-167"><problem>
				<para id="element-827">
					<m:math>
						<m:apply><m:eq/>
							<m:apply>
								<m:fn><m:ci>r</m:ci></m:fn>
								<m:ci>x</m:ci>
							</m:apply>
							<m:apply><m:divide/>
								<m:apply><m:plus/>
									<m:apply><m:times/>
										<m:cn>3</m:cn>
										<m:apply><m:power/>
											<m:ci>x</m:ci>
											<m:cn>2</m:cn>
										</m:apply>
									</m:apply>
									<m:ci>x</m:ci>
								</m:apply>
								<m:apply><m:plus/>
									<m:apply><m:power/>
										<m:ci>x</m:ci>
										<m:cn>2</m:cn>
									</m:apply>
									<m:cn>4</m:cn>
								</m:apply>
							</m:apply>
						</m:apply>
					</m:math>
				</para>
			</problem>
			<solution>
				<para id="element-771"><m:math>
						<m:apply><m:eq/>
							<m:ci>y</m:ci>
							<m:cn>3</m:cn>
						</m:apply>
					</m:math>
				</para>
			</solution>
		</exercise>
	</content>
</document>
