Rearranging formulae

Rearrange 1/u + 1/v = 1/f

to make u the subject of the formula. Give your answer in its simplest form.

There are a number of ways to approach this problem.

By subtracting 1/v on both sides we get 1/u as the subject of the equation:

1/u = 1/f - 1/v

The inverse of the equation can be found to make the subject u:

u = 1/(1/f - 1/v)

This can be simplified by multiplying by fv/fv:

u(fv/fv) = fv/(fv/f - fv/v)

As fv/fv is equal to one, this can be simplified further to give the final answer:

u = fv/(v-f)

RS
Answered by Robert S. Maths tutor

11440 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve 3x+7=1.


A different pattern is made using 20 straight lines and 16 arcs. The straight lines and arcs are made of metal. 20 straight lines cost £12 and the cost of one straight line: cost of one arc = 2:3. Work out the total cost of metal in the pattern.


Factorise x 2 − x − 12


Complete the square on the equation (x^2)-4x-3


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences