Explain the chain rule of differentiation

The chain rule can be used to find more complex derivatives.For example, in the case of: y = (5x + 2)5To find the derivative in the ordinary fashion, one would need to expand the brackets to:y=3125x5+6250x4+5000x3+2000x2+400x+32If you persevere to this point the risk of human error is huge, so clearly an easier method is needed.Enter the chain rule:dy/dx = dy/du * du/dxOne sets u = 5x + 2Now y = u5 and u = 5x + 2Differentiate y wrt u:dy/du = 5u4Differentiate u wrt x:du/dx = 5 Substitute u into dy/dudy/du = 5(5x+2)4Recall that dy/dx = dy/du * du/dx:dy/dx = 5 * 5(5x+2)4dy/dx = 25(5x+2)4The chain rule can be expanded with as many terms as possible, and this is useful when considering real life rates of change:dy/dx = dy/du1 * du1/du2 * du2/du3 * ... * dun-1/dun * dun/dx

Answered by Toby H. Maths tutor

3706 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Using the binomial theorem, find the coefficient of x^4*y^5 in (x-2y)^9.


How do you integrate ln(x) with respect to x?


In a science experiment a substance is decaying exponentially. Its mass, M grams, at time t minutes is given by M=300e^(-0.05t). Find the time taken for the mass to decrease to half of its original value.


Express 4sin(x)+6cos(x) in terms of Rsin(x+a) where R and a are constants to be determined (a should be given in rad).


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences