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# Write down a value of x for which x1/3 is (i) rational, (ii) irrational watch

1. Please can someone show me how to work this out:

Write down a value of x for which x1/3 (x to thepower of one third) is
(i) rational
(ii) irrational.

Thanks
2. (Original post by nettogrof)
Please can someone show me how to work this out:

Write down a value of x for which x1/3 (x to thepower of one third) is
(i) rational
(ii) irrational.

Thanks
For (i), think about a cube root that gives you a whole number. For (ii), thing about one that leaves you with ugly decimals.
3. (Original post by nettogrof)
Please can someone show me how to work this out:

Write down a value of x for which x1/3 (x to thepower of one third) is
(i) rational
(ii) irrational.

Thanks
For i) just write down any number that is a perfect cube and for part ii))= write down a number which is not a perfect cube.
4. too late again ...
5. (Original post by nettogrof)
Please can someone show me how to work this out:

Write down a value of x for which x1/3 (x to thepower of one third) is
(i) rational
(ii) irrational.

Thanks
Hint: if is a surd then it is irrational

so rephrase the questions to

i) find a value of x such that x^1/3 isnt a surd

i) find a value of x such that x^1/3 is a surd

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