Friday

April 18, 2014

April 18, 2014

Posted by **Mae** on Monday, April 19, 2010 at 8:38pm.

1. y= 5^x / x

And the second derivative of:

y= xe^10x

For this question I got up to the first derivative and got this

y = e^10x + 10xe^10x but I can't seem to get the correct answer for the second derivative.

- sorry, the first question isnt showing up properly -
**Mae**, Monday, April 19, 2010 at 8:41pm, its suppose to be

5^squarerootx / x

- Derivatives- Math -
**Reiny**, Monday, April 19, 2010 at 9:48pmy = (5^(√x))/x

I would take ln of both sides

lny = ln (5^(√x))/x

lny = √x(ln5) - lnx

lny = (ln5)(x^1/2) - lnx

y' / y = (1/2)ln5(x^(-1/2)) - 1/x

y = [(5^(√x))/x][(1/2)ln5(x^(-1/2)) - 1/x]

(what a mess!)

for y = xe^10x

y' = e^10x + 10xe^10x is correct, now do it again

y'' = 10e^10x + 10(e^10x + 10xe^10x) , we just did that last part

= 20e^10x = 100xe^10x

**Related Questions**

Calc - 1. Find values of a,b,c, and d such that g(x) = a(x^3)+b(x^2)+cx+d has a ...

Shayna - Find the value of a so that the function f(x) = xe^(ax) has critical ...

Calculus - I need to find the second derivative of y=x(x-1)^1/2. I found the ...

local min - f(x) = x^4 + ax^2 What is a if f(x) has a local minimum at x=5. How ...

calculus - Differentiate both sides of the double angle identify sin 2x= 2 sin x...

calc - derivative of (x^3/6)+(1/2x)? i got (x^2/2)-(1/2x^2) is that correct? and...

Applied Calculus - Find the first and second derivative of the function: x/(7x+...

Calculus (Help) - Also I would like to know how to set this problem up in ...

Quantum mechanics, eigenfunctions! - Determine if the function sin(x)*e^(ax) ...

Pre-cal - Hi, I don't understand this problem also. Find the the relative ...