Find dy/dx when y = x(4x + 1)^1/2

Here we can use the product rule where dy/dx = v du/dx + u dv/dx.We let u = x and v = (4x + 1)1/2 which means we get du/dx = 1 and by using the chain rule we get dv/dx = 1/2(4x + 1)-1/24 which simplifies to dv/dx = 2(4x + 1)-1/2.Plugging these results into the equation for the product rule we get: dy/dx = (4x + 1)1/2 + 2x(4x + 1)-1/2.This result can also be simplified by taking out a factor of (4x + 1)-1/2 to get dy/dx = (4x + 1)-1/2((4x+1) +2x) which proves thatdy/dx = (4x + 1)-1/2(6x +1). Remember that (4x + 1)-1/2 can also be written as the square root on the denominator of a fraction.

RN
Answered by Rebecca N. Maths tutor

6503 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

(Using the Quotient Rule) -> Show that the derivative of (cosx)/(sinx) is (-1)/(sinx).


How to plot quadratic functions, e.g. F(x)= x^2 + 2x +1


Find the values of y such that log2(11y-3)-log2(3)-2log2(​y) = 1


Differentiate 2x^3+23x^2+3x+5 and find the values of x for which the function f(x) is at either at a maximum or minimum point. (Don't need to specify which is which)


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