document.write( "Question 1185294: I am a rational
\n" ); document.write( "function having a vertical asymptote at
\n" ); document.write( "the lines x = 3 and x = -3, and a
\n" ); document.write( "horizontal asymptote at y = 1 . If my
\n" ); document.write( "only x-intercept is 5, and my y-intercept
\n" ); document.write( "is - 5/9 , what function am I?
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Algebra.Com's Answer #816112 by greenestamps(13203)\"\" \"About 
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\n" ); document.write( "The conditions are over-specified; there is no rational function that satisfies all the conditions....

\n" ); document.write( "(1) vertical asymptotes at x=3 and x=-3:

\n" ); document.write( "This means there must be factor(s) of (x-3) and (x+3) in the denominator; and no other linear factors

\n" ); document.write( "\"r%28x%29=a%2F%28%28%28x-3%29%5Em%29%28%28x%2B3%29%5En%29%29\"

\n" ); document.write( "(2) horizontal asymptote at y=1:

\n" ); document.write( "This means the leading terms of the numerator and denominator are the same (same coefficient and same power). That means the coefficient a is 1, and the number of linear factors is the same in numerator and denominator.

\n" ); document.write( "\"r%28x%29=1%2F%28%28%28x-3%29%5Em%29%28%28x%2B3%29%5En%29%29\"

\n" ); document.write( "(3) only x-intercept at x=5:

\n" ); document.write( "The only factor(s) in the numerator are (x-5). From (2), the total number of linear factors in the numerator and denominator must be the same

\n" ); document.write( "\"r%28x%29=%28x-5%29%5E%28m%2Bn%29%2F%28%28%28x-3%29%5Em%29%28%28x%2B3%29%5En%29%29\"

\n" ); document.write( "(4) y-intercept -5/9:

\n" ); document.write( "Set x=0 and see what happens

\n" ); document.write( "\"r%280%29=%28-5%29%5E%28m%2Bn%29%2F%28%28%28-3%29%5Em%29%28%283%29%5En%29%29=-5%2F9\"

\n" ); document.write( "Ignoring signs, with only factors of 5 in the numerator and only factors of 3 in the denominator, the only way to get a y-intercept of 5/9 is with one factor of 5 in the numerator and two factors of 3 in the denominator. But that would make the function

\n" ); document.write( "\"r%28x%29=%28x-5%29%2F%28%28x-3%29%28x%2B3%29%29\"

\n" ); document.write( "And that has both the wrong y-intercept (5/9 instead of -5/9) and the wrong horizontal asymptote (y=0 instead of y=1).

\n" ); document.write( "ANSWER: There is no rational function with all the prescribed conditions

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