Evaluating Absolute Value Functions
The absolute value of a real number x is defined by the following:
x = | x if | x ≥ | 0 |
| x ≤ | 0 |
Note that the effect of taking the absolute value of a number is to strip away the minus sign if the number is negative and to leave the number unchanged if it is nonnegative.
Thus, x≥ 0 for all values of x.
Example
Evaluate various absolute value functions.
1. Evaluate -
2. Is
Evaluate each side of the equation to check your answer. Is x + y =x+ y for all real numbers x and y ?
If not, when will x + y = x+y ?
3. Is
1+3 1+3
Evaluate each side of the equation to check your answer. Investigate with more examples, and decide if you think x / y=x/y
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The solution is +8.
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