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Math help needed (Darn limits)

FakezZ
By FakezZ
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So I need to calculate the limit as x->2 of (4*f(x)^3  - 3*f(x) + 1) / 2*f(x)^3 + 5*f(x)^2 - 6) while knowing that the limit of f(x) as x->2 equals +infinity... Any ideas?

MacBook Pro 15' 2018 (Pretty much the only system I use)

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School? Wait... whut

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School? Wait... whut

Preparing for next year's exams :( I know fuck my life...

MacBook Pro 15' 2018 (Pretty much the only system I use)

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f(x) some function that you're given? Maybe something along the lines of long divison to get a simplified term, dunno tbh. (haven't done limits yet, doing them next year).

 

As @PC-NOOB states, just wanted to give you a good link, khan academy is super for tutorials when it comes to maths, https://www.khanacademy.org/math/differential-calculus/derivative_applications/lhopital_rule/v/introduction-to-l-hopital-s-rule

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Use l'hopitals rule.

 

Edit: l'hopitals rule states that if a limit ends out to be infinity/infinity or 0/0 its equal to the limit of the derivative of the numerator over the derivative of the denominator.

 

Edit 2: Even that is too much work. Just divide both numerator and denom by f(x)^3. Terms of lesser magnitude will end up as 0 and you get 4/2 which is 2.

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Use l'hopitals rule.

 

Edit: l'hopitals rule states that if a limit ends out to be infinity/infinity or 0/0 its equal to the limit of the derivative of the numerator over the derivative of the denominator.

I haven't been taught this yet :( But I'll look it up to see if I can present this legitimately :P

MacBook Pro 15' 2018 (Pretty much the only system I use)

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f(x) some function that you're given? Maybe something along the lines of long divison to get a simplified term, dunno tbh. (haven't done limits yet, doing them next year).

I'm just given it's limit. No word on the function itself, as I don't really need to know more ;) 

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I'm just given it's limit. No word on the function itself, as I don't really need to know more ;)

 

Look at my edit 2.

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I'm just given it's limit. No word on the function itself, as I don't really need to know more ;)

Yeah just go on khan academy sal has great videos when it comes to all things maths.

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Yeah just go on khan academy sal has great videos when it comes to all things maths.

Yup! Thanks! You just saved what seemed to be a long night :P

MacBook Pro 15' 2018 (Pretty much the only system I use)

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Yeah just go on khan academy sal has great videos when it comes to all things maths.

Wow! That's actually a really good resource, thanks!

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just plug in 2 were f(x) is and you will get your answer.

yeah but eventually this leads to inf - inf which is undefined ;)

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Wow! That's actually a really good resource, thanks!

That's what actually got me through my maths course, my teachers were beyond crap. They didn't give you the intution to where the formulas which you use come from. Like integration where you found volumes(pi (y/x)^2 dx/dy, which I didn't see at first but when I did it was easy) were so much easier once I looked at his videos.

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That's what actually got me through my maths course, my teachers were beyond crap. They didn't give you the intution to where the formulas which you use come from. Like integration where you found volumes(pi (y/x)^2 dx/dy, which I didn't see at first but when I did it was easy) were so much easier once I looked at his videos.

@FakezZ I'd also recommend PatrickJMT. That's what got me through first year calculus (Calculus 1 and 2) and my Linear Algebra class.

“The value of a college education is not the learning of many facts but the training of the mind to think”

 

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