Differentiation, Product Rule 3-terms

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RaptorsFan
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Homework Statement



f(x) = (2x-1)(3x-2)(5x+1) d/dx = ?

Note that I am letting (2x-1)(3x-2) = f and 5x+1 = g

Homework Equations



d/dx (fg) = f d/dx g + g d/dx f

The Attempt at a Solution



d/dx y = (2x-1)(3x-2)d/dx(5x+1)+(5x+1)d/dx((2x-1)(3x-2))

= (2x-1)(3x-2)(5)+ (5x+1)(2x-1)d/dx(3x-2)+(3x-2)d/dx(2x-1)
= 5(2x-1)(3x-2) + 3(5x+1)(2x+1) + 2(3x-2)

Can someone validate this answer for me?
 
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RaptorsFan said:

Homework Statement



f(x) = (2x-1)(3x-2)(5x+1) d/dx = ?

Note that I am letting (2x-1)(3x-2) = f and 5x+1 = g

Homework Equations



d/dx (fg) = f d/dx g + g d/dx f

The Attempt at a Solution



d/dx y = (2x-1)(3x-2)d/dx(5x+1)+(5x+1)d/dx((2x-1)(3x-2))

= (2x-1)(3x-2)(5)+ (5x+1)(2x-1)d/dx(3x-2)+(3x-2)d/dx(2x-1)
missed a bracket here, should be
= (2x-1)(3x-2)(5)+ (5x+1)[(2x-1)d/dx(3x-2)+(3x-2)d/dx(2x-1)]
RaptorsFan said:
[
= 5(2x-1)(3x-2) + 3(5x+1)(2x+1) + 2(3x-2)

Can someone validate this answer for me?

final answer looks good to me though, could always check by expanding it out

now that you know it you can make the jump

say
y = fgh

then
y' = f'(gh) + f(gh)' = f'gh + fg'h + fgh'
 
Last edited:
Thank you for the quick response.. much appreciated.