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c3 differentiation help

quotient rule
differentiate
3x^2/(2x-1)^2
i have got it to the form of the quotient rule

(2x-1)^2(6x) - 3x^2 (4(2x-1) /(2x-1)^4
now what
Reply 1
{ 6x(2x-1)^2 - 12(2x-1)x^2 } / (2x-1)^4

= { 6x(2x-1)[(2x-1)-2x] } / (2x-1)^4

You won't need to simplify further.
Reply 2
Original post by Arithmeticae
tbh i wouldn't use the quotient rule here, the product rule with 3x2(2x1)23x^2 (2x-1)^{-2} is easier imo


but its a rational function
Reply 3
Original post by jhpy1024
{ 6x(2x-1)^2 - 12(2x-1)x^2 } / (2x-1)^4

= { 6x(2x-1)[(2x-1)-2x] } / (2x-1)^4

You won't need to simplify further.

but answer is
6x / ( 2x 1 ) 3
Reply 4
Original post by coolgamer
but answer is
6x / ( 2x 1 ) 3

Ah okay, so you need to simplify to get all the marks? In that case, start by expanding the brackets in the numerator.
Original post by coolgamer
quotient rule
differentiate
3x^2/(2x-1)^2
i have got it to the form of the quotient rule

(2x-1)^2(6x) - 3x^2 (4(2x-1) /(2x-1)^4
now what


Moved to Maths section :smile:
Reply 6
Original post by jhpy1024
Ah okay, so you need to simplify to get all the marks? In that case, start by expanding the brackets in the numerator.

for the numerator i got 12x^2-6x-24x^3+3x2 which i think is wrong :/
Reply 7
Original post by coolgamer
for the numerator i got 12x^2-6x-24x^3+3x2 which i think is wrong :/

Here ya go :smile: http://mathb.in/23847
Original post by coolgamer
quotient rule
differentiate
3x^2/(2x-1)^2
i have got it to the form of the quotient rule

(2x-1)^2(6x) - 3x^2 (4(2x-1) /(2x-1)^4
now what


Well first,learn how to use LaTeX

6x(2x1)2(3x2)4(2x1)(2x1)4\dfrac{6x(2x-1)^2-(3x^2)4(2x-1)}{(2x-1)^4}

=

(2x1)(12x26x12x2)(2x1)4\dfrac{(2x-1)(12x^2-6x-12x^2)}{(2x-1)^4}


Cancels easily to the required answer

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