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How do you do this. Please give a full answer and explain why.

How do you do this. Please give a full answer and explain why.-example-1
User Johny Skovdal
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1 Answer

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21 votes

Law of Exponent


\displaystyle \large{ {a}^( - n) = \frac{1}{ {a}^(n) } }

Compare the terms.


\displaystyle \large{ {a}^( - n) = {( - 2)}^( - 3) }

Therefore, a = -2 and n = 3. From the law of exponent above, we receive:


\displaystyle \large{ {( - 2)}^( - 3) = \frac{1}{ {( - 2)}^( 3) } }

Exponent Def. (For cubic)


\displaystyle \large{ {a}^(3) = a * a * a }

Factor (-2)^3 out.


\displaystyle \large{ {( - 2)}^( - 3) = (1)/(( - 2) * ( - 2) * ( - 2))}

(-2) • (-2) = 4 | Negative × Negative = Positive.


\displaystyle \large{ {( - 2)}^( - 3) = (1)/(4 * ( - 2))}

4 • (-2) = -8 | Negative Multiply Positive = Negative.


\displaystyle \large{ {( - 2)}^( - 3) = (1)/( - 8)}

If either denominator or numerator is in negative, it is the best to write in the middle or between numerator and denominators.

Hence,


\displaystyle \large \boxed{ {( - 2)}^( - 3) = - (1)/( 8)}

The answer is - 1 / 8

User Ian Langmore
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