Work out ∛16 as a power of two. (AQA GCSE Higher paper 2017, Q24b)

When you're working with fractional indices, I find the following rhyme really useful:"Fractional indices are like a flower: the bottom's the root, the top's the power".We have a cube root here, which tells us that our root (3) is going to go on the bottom of our fraction, with 1 on the top because the expression is not raised to a power.So first off we convert "cube root 16" to 16 ^1/3 so that we've got our fractional index. So now we can refer to what the question is asking us: to give our answer as a power of 2.We recognize 16 as 2^4 (2x2x2x2), which means we can rewrite what we've got in the following form, using brackets to make everything clearer:16^1/3 = (2^4)^1/3Now recall the rules of indices. We know that when we have a number to a power raised to a second power (as above), we need to multiply the two powers together to get the final answer. So...16^1/3 = 2^(4 x 1/3)= 2^(4/3)


RD
Answered by Ruth D. Maths tutor

19923 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

The new reading for James' electricity bill is 7580, and the old reading is 7510, the price per unit is 13p, how much does James have to pay for his electricity?


how do you solve these simultaneous equations?


If we know that y is directly proportional to x and that when x=1, y=3, then what is the value of x when y=4?


Billy buys 4 adult tickets at £15 each and 2 child tickets at £10 each for show. A 10% booking fee is added to the ticket price. 3% is then added for paying by credit card. Find the total charge for these tickets when paying by card


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:

© 2025 by IXL Learning