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Calculus/differentiation (1 Viewer)

wandering17

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Hii's

can someone pls help me using the quotient rule, differentiate

-2x/(x^2+1)

this, and show working out pls?? i feel like im missing a step or something everytime i do it

thanks! much appreciated
 

Rhinoz8142

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Hii's

can someone pls help me using the quotient rule, differentiate

-2x/(x^2+1)

this, and show working out pls?? i feel like im missing a step or something everytime i do it

thanks! much appreciated
this sis the quotient rule formulae..

(u.v')-(u".v)/ v^2

while

u/v

and there u go..
 

HeroicPandas

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To do quotient rule the most efficiently is to not memorize the formula (well it is the same thing but you don't need to memorize letters)

Here's how I do it..

Step 1: Differentiate top times bottom, MINUS, differentiate bottom times top



Step 2: Draw the fraction bar under step 1



Step 3: Under the fraction bar, write the bottom all squared




Hope you understand :D
 
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shreyansprasad

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-2x/(x^2+1)

Let u=-2x

u'=-2

v=(x^2+1)

v'=2x

Formula= y'=(vu'-uv')/v^2

Hence y'=[(x^2+1)*(-2)-(-2x)(2x)]/(x^2+1)^2

y'=-2x^2-2+4x^2/(x^2+1)^2

y'=2(x^2-1)/(x^2+1)^2
:smile:
 

dan964

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The other method is to avoid quotient rule and to write it as


and then do the product rule which is easier to remember.
 

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