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.

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Answered by Cameron H. Maths tutor

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