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December 14th, 2016, 02:37 AM   #21
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Quote:
 Originally Posted by agentredlum Try breaking up the math tex into several lines so you can more easily identify where the problem is , like this [M ATH] ...... [/M ATH] [M ATH] ..... [/M ATH] [M ATH] ..... [/M ATH]
I did.
Then I simplified it.

Huggs & Kisses December 14th, 2016, 02:41 AM   #22
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Quote:
 Originally Posted by agentredlum Now that I think more about it, there is an easier approach ... Would you agree that $\displaystyle h = \sqrt{|h|} \sqrt{|h|} \text{sgn}(h)$ ? If you do, then $\displaystyle \frac{\sqrt{|h|}}{h} = \frac{\sqrt{|h|}}{\sqrt{|h|} \sqrt{|h|} \text{sgn}(h)}$ Now just cancel common factor $\displaystyle \sqrt{|h|}$ from numerator and denominator to get the final result in my previous post. I originally set on a path and followed it, not the quickest. And I started writing in another window on my phone.
Then used copy paste.
Didn't even see you already simplified it.

Last edited by skipjack; December 14th, 2016 at 10:40 AM. December 14th, 2016, 02:44 AM   #23
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Quote:
 Originally Posted by Luciferis Which could have been realised more easily with. $\displaystyle \frac{\sqrt{|h|}}{h} = \frac{\sqrt{|h|}}{|h|\text{sgn}(h)} = \frac{\sqrt{|h|}}{\sqrt{|h|}\sqrt{|h|}\text{sgn}(h )} = \frac{1}{\sqrt{|h|}\text{sgn}(h)}$
I agree, nice presentation. Note that the introduction of the sgn(h) notation makes it absolutely clear that the 2-sided limit does not exist since h --> 0 from both the positive and the negative.

Last edited by skipjack; December 14th, 2016 at 10:38 AM. Tags abs, calculus, hard, limit, newton, point, problem, quotient, variable Thread Tools Show Printable Version Email this Page Display Modes Linear Mode Switch to Hybrid Mode Switch to Threaded Mode Similar Threads Thread Thread Starter Forum Replies Last Post mathkid Calculus 2 September 16th, 2012 02:31 PM claudillama Calculus 3 January 31st, 2012 07:52 PM netmaxweb Calculus 2 October 15th, 2011 01:11 PM Zeefinity Calculus 2 February 25th, 2011 06:17 AM Zeefinity Calculus 2 February 15th, 2011 08:01 PM

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