How do I work out the exact value of a number which is expressed as an indice, for example 81^-1/4

Firstly, recall the indice rules which are applicable to the question, for example in this question we can use the rules:(x^a)^b = x^abx^-1 = 1/xx^1/2 = square root xSecondly, apply these rules to break down the formula into integers while showing workings, for example:81^-1/4(81^-1/2)^1/2 (1/81^1/2)^1/2(1/9)^1/21/3Note: we could have calculated this question without rule 1 by simply showing (1/81)^1/4. However, if this were a non-calculator question it would be easier to spot square roots.Lastly, show your answer clearly for the marker.

CH
Answered by Cameron H. Maths tutor

3331 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

GCSE Maths - Solve the equation (2x+3)/(x-4) - (2x-8)/(2x+1) = 1 Give your answer to 2 decimal places.


How to factorise quadratic equations?


How does Pythagoras Theorem work?


Make y the subject of the formula x=(2y-1)/(4-y)


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