Find the inverse of: f(x) = (2x + 3)/(x - 4)

To find the inverse of a function, f-1(x):1) set f(x) as y: y =  (2x + 3)/(x - 4)2) swap x and y: x = (2y + 3)/(y -4)3) solve the new equation for y: x(y -4) = 2y + 3 = xy -4x2y - xy = -4x - 3y(2 - x) = -4x -3y = (-4x-3)/(2-x) = f-1(x)

SI
Answered by Sophie I. Maths tutor

5110 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve the quadratic equation 3x^2 + x – 5 = 0 give answers to 3 decimal places


There are 892 litres of oil in Mr Aston’s oil tank. He uses 18.7 litres of oil each day. Estimate the number of days it will take him to use all the oil in the tank.


How do you simplify the following: (3^2)^3


The width of a rectangle is X cm.
 The length is 1·5 cm more than the width.
 The perimeter of the rectangle is 17 cm. Write down an equation satisfied by X
 and solve it to find X.


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