Work out the value of 81^(-1/4) (Non-Calculator)
To answer this question, we have to think about our power rules and use them to slowly simplify this complicated expression:81-1/4 = ((81)1/2)-1/2 (Because ((x)y)z = xyz - one of our 3 power rules)We know that 92 = 81 so if we do a power of 1/2 on both sides we get:9 = 811/2So: 81-1/4 = 9-1/2We can use a similar line of reasoning to get down to:81-1/4= 3-1We also know that a number raised to the power of -1 is equal to 1 divided by that number (x-1 = 1/x)So:81-1/4 = 1/3
RP
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