Question

Hey! more limits help plz:) lim as x->infiniti of (2x^4-x^2-8x)

Answer 1

f(x)->inf as x->infinity
polynomials don't have horiztonal asymptotes

Answer 2

\[\lim_{x \rightarrow \infty} (2x ^{4}-x ^{2}-8x)\]

Answer 3

you know when we take x->inf, we are looking for horizontal asymptotes right?

Answer 4

didnt kno :(..but now i do! horizontal asymptotes are what make equation=0?

Answer 5

no
you know what f(x)=1/x looks like?

Answer 6

so if we changed the eq up a bit n it was \[\lim_{x \rightarrow \infty} (2x ^{4}-x ^{2}+8x ) \div (-5x ^{4}+7)\]

Answer 7

yea

Answer 8

since the powers r the same..the horiz asymptotes r -2/5...is tht the limit?

Answer 9

omg very good

Answer 10

you catch on quick

Answer 11

lol...thnks:)) i try;)

Answer 12

f(x)=1/x has horiztonal asymptote y=0 because as x gets large f(x) is getting closer to zero
another way to say this is
\[\lim_{x \rightarrow \infty} \frac{1}{x}=0\]

Answer 13

what if it was x/1?

Answer 14

x is a polynomial
it doesn't have a horiztonal asymptote
you can say it does not exist or you can say infinity
y=x looks like /
so as x gets large f(x) gets large
as x gets negative large f(x) gets negative large

Answer 15

oh so basically..wen the powers r equal..u jus divide..if the numerator power is larger thn no asym..if denom power is larger..it =0?

Answer 16

yes i think
you mean when the degree of the top=degree of the bottom just take the coeifficient of term with highest exponent on top and put it over the coeifficient of term with highest exponent in bottom.
and yes to the otehr part
if degree higher on top, then no horizontal asymptote
if degree higher on bottom, then y=0 is the horiztonal asymptote

Answer 17

ohhok..yeah thanks a lottt..u wer so wonderfully helpful! lol r u indian?

Answer 18

no im american

Answer 19

lol..jus wonderin cuz..most of the ppl here wer

Answer 20

i seen one indian but i don't really know how many there are
i don't ask lol

Answer 21

haha..gud policy..i asked lik u n amistre....so r u good at integrals?