Given f(x) = (x^4 - 1) / (x^4 + 1), use the quotient rule to show that f'(x) = nx^3 / (x^4 + 1)^2 where n is an integer to be determined.

QUOTIENT RULE: [u(x) / v(x)]' = [u'(x)v(x) - u(x)v'(x)] / v2We have: u(x) = x4 - 1, hence u'(x) = 4x3v(x) = x4 + 1, hence v'(x) = 4x3So we have: [(4x3)(x4 + 1) - (4x3)(x4 - 1)] / (x4 + 1)2Expanding gives us: [4x7 + 4x3 - 4x7 + 4x3] / (x4 + 1)2Giving us a final answer of: [8x3] / (x4 + 1)2, and hence the integer n = 8

TA
Answered by Thomas A. Maths tutor

3183 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

A curve has parametric equations x=t(t-1), y=4t/(1-t). The point S on the curve has parameter t=-1. Show that the tangent to the curve at S has equation x+3y+4=0.


Find the derivative of the following function with respect to x. y = 5e^x−2xsin(x)


What is the chain rule and how is it used?


Express the following as a partial fraction: (4x^2+12x+9) / (x^2+3x+2) .


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