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jdm_eg6
12-04-2006, 08:10 PM
Alright, L'Hoptal's Rule!!

lim (1+10/x)^(x/5)
x->inf

and

lim (8^x)-(7^x) / x
x->o

i neeed help! thanks

jdm_eg6
12-04-2006, 08:21 PM
anyone?

lint
12-04-2006, 09:01 PM
doesn't look like you need help, looks like you want someone to do your homework for you

jdm_eg6
12-04-2006, 09:23 PM
hey lint thanks... oorrr i dont know how to do it, and need a lil bit of help to find out how:

from what i know, maybe use ln in the first example to drop down the exponent, and use product rule to find the derivative. then use L'Hopitals

riander
12-04-2006, 09:25 PM
Read your textbook
they always have examples that will show you exactly how to do it.

liquidboi69
12-04-2006, 09:29 PM
Just download/get Maple...it's like a huge calculator for calc.

Answer is 3ln(2)-ln(7) and (e)^2 just FYI...I hope you're not just copying and taking the easy way out for assignments, because if you don't know this you'll get raped on your final.

Just fyi yea as you know...use lopitals rule and ln all the exponential values down, and differentiate (which is what you're supposed to do in lopitals)

Bongo
12-04-2006, 09:44 PM
Before using L'Hopital's Rule, be sure it is in the proper form.

0/0 or INF/INF. Pick up Elsabrouty's notes too, or download them off the ESS website. PM me if you aren't in Engg.

jdm_eg6
12-04-2006, 09:54 PM
*DOH!* idiot the seond one is easy, dont even need l'hoptals rule, but the questions sais i could.. :poosie:

anyway.

so take the ln of the top you get

xln8-xln7 / x

x's cancel

you get ln8-ln7 which is same as 3ln2-ln7...WOOT! and yes i know of maple...

liquidboi69
12-04-2006, 09:58 PM
Yes thats correct to the above ^ gj.

zieg
12-04-2006, 10:24 PM
I was also gonna suggest maple, lol. But I loaded the page and walked away and just now came back. When I first loaded it there were no replies. Anyway, I guess you fixed it.

jdm_eg6
12-04-2006, 10:38 PM
i still dont get how e^2 is an answer, i know there is sum trick SOMWHERE i just cant find her!

jdm_eg6
12-04-2006, 10:50 PM
well 70% on the assignment, and ill leave it at that, i just CANT get the rest of them.

i will ask the proff about them tomorrow tho!:thumbsup: