Simple derivative

AGlas9837

Junior Member
Joined
Jan 23, 2008
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I'm given S=2x+288/x and told the derivative is dS/dx = 2-288/x^2. I'm not following how you get this derivative here. (This has to do with an optimization problem where you are looking for a minimum sum.)
 
Hello, AGlas9837!

You've new at differentiation?


I’m given S=2x+288x and told the derivative is: dSdx=2288x2\displaystyle \text{I'm given }S\:=\:2x+\frac{288}{x}\text{ and told the derivative is: }\frac{dS}{dx} \:=\: 2-\frac{288}{x^2}

Exactly where is your difficulty?


The derivative of 2x is 2.\displaystyle \text{The derivative of }2x\text{ is }2.


For the derivative of -288x\displaystyle \text{For the derivative of -}\frac{288}{x}

. . (1) use the Quotient Rule, or\displaystyle \text{(1) use the Quotient Rule, or}

. . (2) use the Power Rule on -288x1\displaystyle \text{(2) use the Power Rule on -}288x^{-1}

 
I see now...using the quotient rule it makes sense. Thank you! (First semester of calculus....all of my algebra was taken a long time ago)
 
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