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The absolute value function simply returns when is positive and when is negative, ensuring the result is non-negative. However, the minus sign outside the absolute value negates the result of the absolute value. Therefore, results in for all . Hence, the original expression evaluates to .
Determine the absolute value of the following number:
\( \left|18\right|= \)
Great question! The absolute value always gives us a positive result (or zero). Whether z is positive or negative, is always non-negative. The negative sign outside the absolute value then makes the final result negative.
They're actually the same thing! Both equal when z ≥ 0 and when z < 0. The absolute value removes negative signs from inside, while the minus outside negates the whole expression.
Only when z is negative! If z < 0, then (positive), so which is positive since z is negative.
Step by step: . The absolute value of 6 is 6, then the negative sign outside makes it -6. This matches our general answer of -2z = -2(3) = -6!
When z = 0: . Zero is neither positive nor negative, so the result is just 0. Our formula -2z still works: -2(0) = 0.
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