- f(x)=((x+1)(x-2))/(x^2 -5x +1)
- f(x)= (x2 − 1)(x^3 + 3x^2/x^2 + 2)

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- October 30th 2008, 11:29 AMhenrihow to find the derivatives

- f(x)=((x+1)(x-2))/(x^2 -5x +1)
- f(x)= (x2 − 1)(x^3 + 3x^2/x^2 + 2)

- October 30th 2008, 11:48 AMplm2e
- October 30th 2008, 11:56 AMhenri
For 1 my answer is: (-14x +16x +9)/(x^2 -5x +1)^2

Is this Correct?

For 2 my answer is: (2x^6 +4x^4 +6x^5 +4x +6x^3 -6x^2-6x)/(x^2 +2)^2 - October 30th 2008, 11:57 AMplm2e
what is x2 on your 2nd problem

- October 30th 2008, 12:00 PMhenri
x^2 is the denominator because it has to be squared

- October 30th 2008, 12:06 PMplm2e
- October 30th 2008, 12:08 PMplm2e
- October 30th 2008, 12:11 PMhenri
why is the numerator's derivative x-1 instead of 2x-1 and the same for the denominator

- October 30th 2008, 12:12 PMhenri
Sorry for my error but the second one is (X^2 -1)(. . .)

- October 30th 2008, 12:17 PMplm2e
- October 30th 2008, 12:25 PMhenri
no problem thanks for all. by the way is there an easier way to put in mathematical symbols in this program? I see other posts with better formats.

- October 30th 2008, 12:31 PMplm2e
prob 2:

i got:

y= [x^5 +3x^4 -x^3 -3x^2] / (x^2 +2)

y'= [(x^2 +2)(5x^4 +12x^3 -3x^2 -6x) - (x^5 +3x^4 -x^3 -3x^2)(2x)] / (x^2 +2)^2

.....

= [3x^6 + 6x^5 + 9x^4 + 24x^3 - 6x^2 - 12x] / (x^2 +2)^2 - October 30th 2008, 12:33 PMplm2e
not sure about the symbols. Im new to this site using it for stats help. Thought i would try one i knew how to do