Difference between revisions of "Absolute Value Functions"

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In mathematics, the absolute value or modulus of a real number x, denoted |x|, is the non-negative value of x without regard to its sign. Namely, |x| = x if x is positive, and |x| = −x if x is negative (in which case −x is positive), and |0| = 0. For example, the absolute value of 3 is 3, and the absolute value of −3 is also 3. The absolute value of a number may be thought of as its "distance from zero".
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==Introduction==
 
[[Image:Absolute value.svg|thumb|The [[graph of a function|graph]] of the absolute value function for real numbers]]
 
[[Image:Absolute value.svg|thumb|The [[graph of a function|graph]] of the absolute value function for real numbers]]
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In mathematics, the absolute value or modulus of a real number x, denoted |x|, is the non-negative value of x without regard to its sign. Namely, |x| = x if x is positive, and |x| = −x if x is negative (in which case −x is positive), and |0| = 0. For example, the absolute value of 3 is 3, and the absolute value of −3 is also 3. The absolute value of a number may be thought of as its "distance from zero". The absolute value function f(x) = |a| can be expressed as a piecewise function, where f(x) = a when a ≥ 0, and f(x) = -a when a < 0. We can use this to help us visualize and graph other absolute value functions.
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Here are some examples of absolute value functions:
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* <math> g(x) = |5x + 5| </math>. 5x + 5 ≥ 0 when x ≥ -1, and 5x + 5 < 0 when x < -1. So, g(x) = 5x + 5 when x ≥ -1, and g(x) = -5x - 5 when x < -1.
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* h(x) = ||
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==Resources==

Revision as of 11:51, 15 September 2021

Introduction

The graph of the absolute value function for real numbers

In mathematics, the absolute value or modulus of a real number x, denoted |x|, is the non-negative value of x without regard to its sign. Namely, |x| = x if x is positive, and |x| = −x if x is negative (in which case −x is positive), and |0| = 0. For example, the absolute value of 3 is 3, and the absolute value of −3 is also 3. The absolute value of a number may be thought of as its "distance from zero". The absolute value function f(x) = |a| can be expressed as a piecewise function, where f(x) = a when a ≥ 0, and f(x) = -a when a < 0. We can use this to help us visualize and graph other absolute value functions.

Here are some examples of absolute value functions:

  • . 5x + 5 ≥ 0 when x ≥ -1, and 5x + 5 < 0 when x < -1. So, g(x) = 5x + 5 when x ≥ -1, and g(x) = -5x - 5 when x < -1.
  • h(x) = ||

Resources