Use the chain rule to find the derivative

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Mathysics
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Homework Statement


f(x) = ((x^2+2)^2)/(x+2)^1/2
Use the chain rule to find the derivative

Homework Equations


None


The Attempt at a Solution


((x^2+2)^2)(x+2)^-1/2

PS: Answer in the book is 3x((x^2+2)^1/2)

I have no idea how they get it there, would like some help, thx!
 
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Mathysics said:

Homework Statement


f(x) = ((x^2+2)^2)/(x+2)^1/2
Use the chain rule to find the derivative

Homework Equations


None


The Attempt at a Solution


((x^2+2)^2)(x+2)^-1/2

PS: Answer in the book is 3x((x^2+2)^1/2)

I have no idea how they get it there, would like some help, thx!
It looks like you completely missed the fact that this is a quotient (use the quotient rule first). As part of using the quotient rule, you'll need the chain rule.
 


Mark44 said:
It looks like you completely missed the fact that this is a quotient (use the quotient rule first). As part of using the quotient rule, you'll need the chain rule.

ohh thx! I will try it again (reserved)
 


Or, since the product rule is (to me anyway) less complicated than the quotient rule, write your function as [itex]f(x) = (x^2+2)^2(x+2)^{-1/2}[/itex] and use the product rule, together with the chain rule.