Differentiation using product rule?

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Homework Help Overview

The discussion revolves around differentiating the function p(x) = ((x+5)^2)*((x+3)^7) using the product rule. Participants are exploring the differentiation process and simplification of the resulting expression.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to apply the product rule for differentiation but questions the correctness of their result. Some participants suggest simplifying the expression further by factoring out common terms.

Discussion Status

Participants are actively engaging in refining the differentiation result and discussing various simplification strategies. There is acknowledgment of the initial differentiation being correct, but differing opinions on the best way to simplify the expression further.

Contextual Notes

There is an emphasis on ensuring that algebraic manipulation is performed correctly, with some participants expressing concern over the clarity and accuracy of the algebra used in simplifications.

steve snash
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Homework Statement


Differentiate the following function with respect to x,
p(x) = (( x+5 )^2)*(( x+3 )^7)


Homework Equations


well the product rule is,
p(x)=(f)*(g)
p'(x)= (f')*(g)+(g')*(f)
and general differentiation is,
p'(x)=n(f)^(n-1)*n(g)^(n-1)

The Attempt at a Solution


well i used the product rule and got
(2(x+5))*((x+3)^7)+(7(x+3)^6)*((x+5)^2)
but this is said to be wrong how do i simplify it more or what have i done wrong?
 
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What you did is right. They probably just want you to pull out the common factors to simplify it more.
 
so i could go,
(2*x+10)*(x+3)^7+(7x+21)*(x+5)^2
then
(3x+13)^7+(8x+26)^2
 
steve snash said:
so i could go,
(2*x+10)*(x+3)^7+(7x+21)*(x+5)^2
then
(3x+13)^7+(8x+26)^2

Your algebra is looking pretty seriously awful there. Whoa. Just factor out (x+5)*(x+3)^6 and collect the rest. Try and use only real algebra this time, and not just random symbol rearrangment, ok?
 
so it works out to be,
((x+3)^6)*((9x^2)+(86x)+205)
cheers for the help
 
steve snash said:
so it works out to be,
((x+3)^6)*((9x^2)+(86x)+205)
cheers for the help

That's one version. You could also write it as (x+3)^6*(x+5)*(9x+1). Whatever works, like I said your initial differentiation was correct as well.
 

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