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toshi (26)

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differentiate the following :

                 1
--------------------------------------
       (x-3)  (x-2)  (x-1)   

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umang (229)

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I think its 12x - 3x^2 - 11 divided by (x-1)^2 (x-2)^2 (x-3)^2
Pls confirm !!!

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vasanth (2315)

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i believe the ans is
-1/[2(x-3)^2] - 1/[2(x-2)^2] - 1/[(x-1)^2]
 
 
plzzzzz tell me if i'm wrong
 
 
 
 
 
newayzz gimme ur votes

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umang (229)

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Hey toshi ,
can u pls tell the correct answer ???

Umang
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vasanth (2315)

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hey umang
i tried solvin my equation and i got  a biquadratic expression.......
 
can u plzzzzz work it out

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umang (229)

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Hey vasanth ,
I solved the denominator and then applied the quotient rule of differentiation . I hope my method is correct ?
Pls check and reply !!!!

Umang
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dada (0)

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hey umang i'd b greatful if u solve it here 4 me....
 
i'm not able to get ur solution.....
plzzzz write it down so tat i can correct my mistake if i'm wrong.....
 
 
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vish0001 (493)

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take logarithm and then solve '!!! it's damn easy then !



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n_teja2007 (42)

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f(x) = f1(x) * f2(x) * f3(x)

f'(x) = f1'(x) * f2(x) * f3(x) + f1(x) * f2'(x) * f3(x) + f1(x) * f2(x) * f3'(x)

hence the answer

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yahiyafirdous (293)

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Let y= 1/[(x-1)(x-2)(x-3)]
 
logy= -[log(x-1)+log(x-2)+log(x-3)]
 
(1/y)dy/dx= -[1/(x-1) +1/(x-2)+1/(x-3)]
 dy/dx= -[1/(x-1) +1/(x-2)+1/(x-3)] y
  dy/dx= -[(x-2)(x-3)+(x-1)(x-3)+(x-1)(x-2)]
dy/dx=-[3x2 -12x +11]   Ans
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magiclko (4210)

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well, vasant is almost right, jst li'l mistakes of sign!!!
converting the given fraction into partial functions....
y = 1/[(x-3)  (x-2)  (x-1)] = [1/ { 2 (x-3) }] - [1/ {x-2}] + [1/ { 2 (x-1) }]
Now we can differntiate it easily,
y' =  [-1/ { 2 (x-3)2 }] + [1/ {x-2}2 ] - [1/ { 2 (x-1)2 }]

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edison (4929)

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If  y= 1/[(x-1)(x-2)(x-3)]
 
Taking log on both the sides we obtain
 
lny= -[ln(x-1)+ln(x-2)+ln(x-3)]
 
differentiating both the sides w.r.t x we obtain
 
(1/y)dy/dx= -[1/(x-1) +1/(x-2)+1/(x-3)]
 
 dy/dx= -[1/(x-1) +1/(x-2)+1/(x-3)] y
 
  dy/dx = -[(x-2)(x-3)+(x-1)(x-3)+(x-1)(x-2)]
 
  dy/dx = -[3x2 -12x +11] 

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sudeep.kumar (611)

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Both firdous and teja have outlined the correct approach, but the one used by edision (same as firdous) is the best.

Sudeep Kumar
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umang (229)

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hey all !
Please tell the mistake in my solution . I have solved the denominator and then applied quotient rule . But the answer I am getting is different . I am getting (x-1)^2 (x-2)^2 (x-3)^2 in the denominator . Numerator is same . Pls explain !!!!!!!

Umang
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