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alexthomas
 one year ago
Find the limit if it exists...
alexthomas
 one year ago
Find the limit if it exists...

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alexthomas
 one year ago
Best ResponseYou've already chosen the best response.0dw:1372210588807:dw

alexthomas
 one year ago
Best ResponseYou've already chosen the best response.0the radical is over the (+x) as well if not clear

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1You want to multiply by the conjugate

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1\[\large \lim_{x \rightarrow \infty} \ \frac{\sqrt{25x^2+x}5x}{1} \cdot \frac{\sqrt{25x^2+x} +5x}{\sqrt{25x^2+x} +5x}\]

alexthomas
 one year ago
Best ResponseYou've already chosen the best response.0i'm getting 25+x25x^2 /radical 25x^2+x +5x

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1\[\large \lim_{x \rightarrow \infty} \ \frac{(25x^2+x)(5x)^2}{\sqrt{25x^2+x} +5x} \]

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1\[\large \lim_{x \rightarrow \infty} \ \frac{x}{\sqrt{25x^2+x} +5x}\]

alexthomas
 one year ago
Best ResponseYou've already chosen the best response.0good i got that too it cant be simplified any further right?

dumbcow
 one year ago
Best ResponseYou've already chosen the best response.0i would use l'hopitals rule now

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1LH Rule: \[\large \frac{ f'(x)}{g'(x)}\]

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1Since if we took the limit to infinity we'd get \(\large \frac{\infty}{\infty}\)

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1Can you tell me what the derivative of \(\large \sqrt{25x^2 +x} +5x\) is?

alexthomas
 one year ago
Best ResponseYou've already chosen the best response.0dw:1372212305372:dw

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1Not exactly.. We have \(\large \sqrt{25x^2+x}+5x\) right? That can be rewritten as \(\large (25x^2 +x)^{1/2}+5x\) Using chain rule: \(\large \frac{1}{2\sqrt{25x^2+x}} \cdot (50x +1) +5\) Simplify : \(\large \frac{50x+1}{2\sqrt{25x^2+x}} +5\)

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1So now we'll have... \[\huge \lim_{x \rightarrow \infty} \ \frac{\frac{1}{50x+1}}{2\sqrt{25x^2+x}+5}\]

alexthomas
 one year ago
Best ResponseYou've already chosen the best response.0i got the answer to be 1/10 thank you

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1Can you explain to me how you got that? :o

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1what i got was \[\large \lim_{x \rightarrow \infty} \ \frac{1}{(100x+2)(\sqrt{25x^2+x}+5)} = 0 \]

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1An unforseen method of approach!

dan815
 one year ago
Best ResponseYou've already chosen the best response.0what shud we subtract there

dan815
 one year ago
Best ResponseYou've already chosen the best response.0i dunno for some reason i feel like it cant be 0

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1How do you factor out a 5x from \(\large \sqrt{25x^2+x}\) ?

dan815
 one year ago
Best ResponseYou've already chosen the best response.0its tough sqrt roots arent friendly

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1HOW DO YOU GET 1/10???? thats what i wanted to know! and then the guy disappeared lol.

dan815
 one year ago
Best ResponseYou've already chosen the best response.0i didnt im just saying that answer looks right lol

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1secret methods....hidden treasures.

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1I want toknow this.

dan815
 one year ago
Best ResponseYou've already chosen the best response.0maybe we can rewrite this as some other known function base like hyperbola?

RaphaelFilgueiras
 one year ago
Best ResponseYou've already chosen the best response.2dw:1372215364565:dw

RaphaelFilgueiras
 one year ago
Best ResponseYou've already chosen the best response.2dont need to use L'H,just put x in evidence

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1im so confused.....wait a minute...

dan815
 one year ago
Best ResponseYou've already chosen the best response.0shudda known it was something simple

dan815
 one year ago
Best ResponseYou've already chosen the best response.0basically hes saying the highest exponents there will just be root(25x^2) and 5x so we can still divide everything by x

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1Oh...hm. Let me try this.

RaphaelFilgueiras
 one year ago
Best ResponseYou've already chosen the best response.2dw:1372215619036:dw

dan815
 one year ago
Best ResponseYou've already chosen the best response.0@whpalmer4 show us the way

RaphaelFilgueiras
 one year ago
Best ResponseYou've already chosen the best response.2dw:1372215784059:dw

RaphaelFilgueiras
 one year ago
Best ResponseYou've already chosen the best response.2i think that is not right

dan815
 one year ago
Best ResponseYou've already chosen the best response.0u shud have +5 there instead of last 0, and ur diving by x that is the higest power

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1Oh YEAH. 5x/x * my bad.

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1I forgot the x...... 1/10 is the answer,lol. whoops.

RaphaelFilgueiras
 one year ago
Best ResponseYou've already chosen the best response.2@dan815 x²(25+1/x)= 25x²+x

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1you were on the right track \[\large \lim_{x \rightarrow \infty} \ \frac{x}{\sqrt{25x^2+x} +5x} = \large \lim_{x \rightarrow \infty} \ \frac{1}{\frac{\sqrt{25x^2+x} +5x}{x}}\]

RaphaelFilgueiras
 one year ago
Best ResponseYou've already chosen the best response.2dw:1372216149948:dw

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1\[\large \lim_{x \rightarrow \infty} \ \frac{x/x}{\sqrt{25x^2/x^2 +x/x^2}+5x/x}\]\[\large \frac{1}{\sqrt{25+0}+5} =\frac{1}{10} \]

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1When lim tends to infinity, divide by highest exponent. When lim tends to a number, use LH rule :D

RaphaelFilgueiras
 one year ago
Best ResponseYou've already chosen the best response.2just take care because if x goes to  inf x=x

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1yeah. I understand :)

RaphaelFilgueiras
 one year ago
Best ResponseYou've already chosen the best response.2sqrt(x²)=x not x; we do that only because we know x is positive(inf)

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1You divide everything under a square root by the highest power underneath the root, and all the other x's get divided by the value of x that is dependent on the behavior of the function, (i.e if x tends to positive or negative infinity)

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1lol we're saying the same thing....2 different ways :(

RaphaelFilgueiras
 one year ago
Best ResponseYou've already chosen the best response.2if x goes to  inf the result isn't the same

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1yes,so if x goes to inf, x takes on neg values.... hence we divide by x instead of x.

whpalmer4
 one year ago
Best ResponseYou've already chosen the best response.1\[\large \large \lim_{x \rightarrow \infty} \ \frac{1}{\frac{\sqrt{25x^2+x} +5x}{x}} = \frac{1}{5+ \sqrt{\lim_{x\rightarrow \infty} \ \frac{25x^2+x}{x^2}}} \]\[= \frac{1}{5+ \sqrt{\lim_{x\rightarrow \infty} \ \frac{50x+1}{2x}}}\]by L'Hopital \[=\frac{1}{5+\sqrt{25}}\]

Jhannybean
 one year ago
Best ResponseYou've already chosen the best response.1Tried @whpalmer4 's way myself just now. REALLY interesting hahaha
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