I have the calculator portion of my Ch. 3 Calculus test tomorrow, titled Derivatives. I'm doing a review sheet right now, and am stuck on a problem. If f(x) = 13 - 8x + √2x² + 1 and f '(r) = 4 find r.
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Just take the derivative of your 1st function and set it equal to 4 and replace x with r. Solve for r.
I think I messed up taking the derivative of √2x² because f ' (x) came out to be like -6 What is the derivative of √2x² is it just 2?
Originally Posted by JBknights10 I think I messed up taking the derivative of √2x² because f ' (x) came out to be like -6 What is the derivative of √2x² is it just 2? No, the derivative of $\displaystyle \sqrt{2} \, x^2$ with respect to x is $\displaystyle 2 \sqrt{2} \, x$.
Originally Posted by mr fantastic No, the derivative of $\displaystyle \sqrt{2} \, x^2$ with respect to x is $\displaystyle 2 \sqrt{2} \, x$. Thank you. I'm new I need to figure out how to get problems to show up so well with the math tags.
Originally Posted by JBknights10 Thank you. I'm new I need to figure out how to get problems to show up so well with the math tags. http://www.mathhelpforum.com/math-he...-tutorial.html
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