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Given an expression (either a^-k or 1/a^-k) with a negative index, rewrite it with a positive index.

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The variable a and the index k are randomised.

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Part of HELM Book 1.2

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Write each of the following using a positive index. Use Key Point 9. (To enter $\\dfrac{1}{m^6}$ type 1/m^(6) )

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(a) $\\var{expr[0]}=\\dfrac{1}{\\var{expression(letterchoice[0])}^{\\var{idx[0]}}}$

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(b) $\\var{expr[1]}=\\dfrac{1}{\\var{expression(string(numberchoice[0]))}^{\\var{idx[1]}}}$

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(c) $\\displaystyle{\\var{expr[2]}}=\\var{expression(letterchoice[1])}^{\\var{idx[2]}}$

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(d) $\\displaystyle{\\var{expr[3]}}=\\var{expression(string(numberchoice[0]))}^{\\var{idx[3]}}$

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Is the answer a fraction?

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(a) $\\displaystyle{\\var{expr[0]}} =$ [[0]]

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(b) $\\displaystyle{\\var{expr[1]}} =$ [[1]]

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(c) $\\displaystyle{\\var{expr[2]}} =$ [[2]]

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(d) $\\displaystyle{\\var{expr[3]}} =$ [[3]]

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