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Advanced Math/Application of L' Hospital's Rule

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Question
In my mathbook this section deals with L'Hospital's Rule but I can't figure out how to use it here.

Problem:
If F' is continuous , F(2) = 0 and F'(2) = 7

evaluate::
limit as x->0 of [F(2+3x) + F(2+5x)] / x
thanks

Answer
Hi Charles,

I got this question from the Question Pool, so it might be a bit late.  

Just calculating the limit gives you F(2)+F(2) = 0 / 0. That's where L'Hospital's Rule comes in.

lim   [F(2+3x) + F(2+5x)] / x
x->0          

= lim Dx F(2+3x) + Dx F(2+5x) / Dx x
= (7 + 7) /1  
= 14

I hope this helps,
Jack

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Jack Cheng

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I can answer most questions in Math up to single-variable Calculus, including infinite series. I like to think very much, so questions with a lot of twists and turns are highly welcomed! Mathematical questions related to computer science are also highly welcomed! I can also answer some basic questions in discrete mathematics (logics, sets, some algorithms, basic number theory). I am also studying physics (mechanics in particluar), so I am willing to answer some questions relating to it.

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Majoring in Mathematics.

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I am sophomore/junior status in college working towards bachelor's degrees in Computer Science and Mathematics.

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