Differentiate y= (2x+1)^3. [The chain rule]

For maths questions I feel that getting your head around the concepts are difficult but once achieved allow you to comfortably answer a wide range of questions. Therefore for maths tuition I think it is important to find a method that works for the student and then practice using it through multiple questions.  

Obviously it is easier to discuss concepts face-to-face however for this example I've found a four step process helps me answer questions on the chain rule. 

1) Differentiate the thing in the brackets

 y = 2x+1    -->      dy/dx = 2

2) Multiply that by the induction outside the bracket

2 X 3 = 6

3) Stick this number before the initial bracket

6(2x+1)^3

4) Minus 1 off the initial indicy

6(2x+1)^2 

So dy/dx = 6(2x+1)^2

This is just one method. There is another one substituting U into the equation and then saying [du/dx X dy/du = dy/dx]. I would go through both methods with the students so they can use the one that works for them. 

JJ
Answered by James J. Maths tutor

19527 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Curve C has equation x^2 - 3xy - 4y^2 + 64 = 0. a) find dy/dx in terms of x and y. b) find coordinates where dy/dx=0.


Find the exact value of the gradient of the curve y = e^(2- x)ln(3x- 2). at the point on the curve where x = 2.


Solve the differential equation dx/dt = -2(x-6)^(1/2) for t in terms of x given that x = 70 when t = 0.


A small stone is projected vertically upwards from a point O with a speed of 19.6m/s. Modelling the stone as a particle moving freely under gravity, find the length of time for which the stone is more than 14.7 m above O


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