What did you get for Dx[(2x-5)^4] and Dx[x^3] ?(n/t)

Posted by Subhotosh Khan on November 11, 2002 at 07:27:25:

In Reply to: Re: hints posted by tim on November 10, 2002 at 20:58:04:

:
: : you must use a combination of rules.

: : start with the product rule (since you are multiplying things), then use power rule.

: : note that you have x^3(2x-5)^4

: : so you have a product of x³ and (2x-5)⁴

: : so D_x[x^3(2x-5)^4]

: : = x^3*D_x[(2x-5)^4] + (2x-5)^4*D_x[x^3]

: : where D_x[y] means the derivative of y with respect to x.

: I can get that far. then im stuck. when i check it on the calculator i get x²(2x-5)^3(14x-15).
: and i can't get that answer.

Re: What did you get for Dx[(2x-5)^4] and Dx[x^3] ?(n/t) tim 17:19:08 11/11/02 (2)
- Well then .... Subhotosh Khan 17:44:32 11/11/02 (1)
  - i can't belive i couldn't get that tim 19:15:41 11/11/02 (0)