Ask your own question, for FREE!
Mathematics 22 Online
OpenStudy (anonymous):

rf

OpenStudy (misty1212):

HI!!

OpenStudy (misty1212):

this looks like it could be hard, but maybe not too hard

OpenStudy (anonymous):

so its (x-5) at the bottom

OpenStudy (misty1212):

yes

OpenStudy (misty1212):

and the asymptote is \(y=x^2-3x\) so when you divide the top by the bottom you should get \(x^2-3x\) with some remainder

OpenStudy (misty1212):

lets call the numerator \(p(x)\) so that \[\frac{p(x)}{x-5}=x^2-3x+\frac{R}{x-5}\] or more simply \[p(x)=(x^2-3x)(x-5)+R\]

OpenStudy (misty1212):

now we can replace \(x\) by \(-1\) and set the result equal to \(3\) and see if we can solve for \(R\)

OpenStudy (misty1212):

you with me so far?

OpenStudy (misty1212):

cause we are almost done

OpenStudy (anonymous):

yes

OpenStudy (misty1212):

ok if we replace \(x\) by \(-1\) in the denominator, we get \(-1-5=-6\)

OpenStudy (misty1212):

that means the numerator has to be \(-18\) so that the fraction will be \[-\frac{18}{-6}=3\]

OpenStudy (misty1212):

\[p(x)=(x^2-3x)(x-5)+R\] put \(x=-1\) set the result equal to \(-18\) and solve for \(R\)

OpenStudy (misty1212):

in other words, solve \[p(-1)=((-1)^2-3(-1))(-1-5)+R=18\] for \(R|)

OpenStudy (misty1212):

ooops \[p(-1)=((-1)^2-3(-1))(-1-5)+R=-18\]

OpenStudy (misty1212):

there may have been an easier way to do it, but i don't know it you get \[4\times (-6)+R=-18\] or \[-24+R=-18\]

OpenStudy (anonymous):

so what is the rational function

OpenStudy (misty1212):

we get \(R=6\) right?

OpenStudy (anonymous):

yep

OpenStudy (misty1212):

that means the numerator is \[p(x)=(x^2-3x)(x-5)+6\]

OpenStudy (misty1212):

multiply that out, combine like terms etc, and you answer will be that polynomial over \(x-5\)

OpenStudy (misty1212):

if you do it correctly you will get \[\frac{x^3-8 x^2+15 x+6}{x-5}\]

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!