Hello, I have those limit question to answer. (I applied Hospital Law)(adsbygoogle = window.adsbygoogle || []).push({});

1) lim cotgx / lnx

x-> 0+

Heres what I did:

1) form infinite/infinite;

-(cosec x)^2 / (1/x) = -2cosecx*-cosecx*cotgx / (-1x^-2) = -2(cosecx)^2 *cotgx * x^2 = 0

(wrong answer, I dont understand what's wrong with what I did)

2nd question: I got the answer right but I want to know if I can do what I did or it was just luck..

lim x^100 / e^x

x-> +oo (inf.)

what I did: y = e^x, ln y = x. so

x^100 / y = ln x^100 / lny = 100lnx/lny = 100/x = 0

and question 3)

lim ln(sinx) / ln(tgx)

x-> 0+

what I did:

(cosx/sinx) / (sec x)^2 = cosx/sinx * 1/(sec x)^2 = (cosx)^3 / sinx

= -3 cosx *sinx (derivat.) = -3*0 = 0 (wrong answer, answer is 1 from the booK)

Any help would be greatly appreciated

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# Homework Help: Simple limit questions help (work is there)

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