Determine the stationary points of y=(5x^2)/(lnx)

Differentiate y with respect to x using quotient rule:y'=[(1/x)(5x^2)-(10x)(lnx)]/(lnx)^2 =[5x-10xlnx]/(lnx)^2Stationary points occur when y'=0, so when y'=0 we have:5x-10xlnx = 0x(5-10lnx)=0So x=0 or 5-10lnx=0But when x=0, lnx is undefined, so there is no y value at x=0. So x cannot equal 0.Therefore: 5-10lnx=0 x=e^0.5Substitute back into y, we obtain:y=5e/0.5 = 10eSo Sationary Point is: (e^0.5, 10e)

JL
Answered by Jimmy L. Maths tutor

3935 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Given a table showing grouped data and the frequency of each class, find the median Q2


There is a Ferris wheel where the passengers are placed 10m away from the centre. At what speed must they be moving in order for them to feel completely weightless at the top of the wheel.


Define the derivative of a function f(x) and use this to calculate the derivative of f(x)=x^n for positive integer n.


Can you give an example of using the chain rule for differentiation? Example: Let y=(6 + 2x + 2x^2)^3, find dy/dx.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning