Understand the exponent: Understand the exponent.The exponent −21 indicates that we need to find the reciprocal of the square root of 7.
Find the square root: Find the square root of 7.The square root of 7 is the number that, when multiplied by itself, gives 7. This is not a perfect square, so it cannot be simplified to an integer or simple fraction.
Take the reciprocal: Take the reciprocal of the square root of 7. The reciprocal of a number is 1 divided by that number. So, the reciprocal of the square root of 7 is 1 divided by the square root of 7.
Write the final answer: Write the final answer.The final answer is the reciprocal of the square root of 7, which is written as 71 or 7−1.
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