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If k is a positive integer, then (- 7^{k})^{- 1} + (- 7^{- k}) =

Explanation	Calculations	Help
$We simplify $\textbf{"(-7^k)^{-1}"}$ by recognizing that raising to a negative exponent gives the reciprocal and then apply the exponent rule.$	$(- 7^{k})^{- 1} = (- 1)^{- 1} \times 7^{- k} = - 1 \times 7^{- k} = - 7^{- k}$	Theory & Tactics Method Card CALC3-A Click to view full details
$We simplify $\textbf{"(-7^{-k})"}$ by recognizing it is the negative of .$	$(- 7^{- k}) = - 7^{- k}$
$We add the two like terms, both equal to - 7^{- k}, to combine them into a single expression.$	$- 7^{- k} + (- 7^{- k}) = - 2 \times 7^{- k}$

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C

If k is a positive integer, then (- 7^{k})^{- 1} + (- 7^{- k}) =

Explanation	Calculations	Help
$We simplify $\textbf{"(-7^k)^{-1}"}$ by recognizing that raising to a negative exponent gives the reciprocal and then apply the exponent rule.$	$(- 7^{k})^{- 1} = (- 1)^{- 1} \times 7^{- k} = - 1 \times 7^{- k} = - 7^{- k}$	Theory & Tactics Method Card CALC3-A Click to view full details
$We simplify $\textbf{"(-7^{-k})"}$ by recognizing it is the negative of .$	$(- 7^{- k}) = - 7^{- k}$
$We add the two like terms, both equal to - 7^{- k}, to combine them into a single expression.$	$- 7^{- k} + (- 7^{- k}) = - 2 \times 7^{- k}$

Scroll horizontally to view all columns

C