Originally Posted by

**haebinpark** Hi,

I'm having problems with few limit questions

lim x-> -inf (x^3 - 1)/[(2x^2)(x-1)]

lim x-> -inf (6x^2 - x +3)/(3-x-4x^2)

lim x-> -inf (sqrt 16x^2 - 5x)/(3x+1)

i have to solve these problems by divide by highest power in denominator thingy

but i am really confusing about the sign in denominator.

what i am thinking is that:

for the first one, i think i should multiply by -1 for denominator because the highest power is 3 ?

for the second one, i think i should leave it as it is because the highest power is 2 ?

for the third one, i think i should multiply by -1 for denominator because the highest power is 1 ?

am i right? if not, could you point me out where i went wrong ?