How do you prove a|≥ a ?
Thanks.
Thanks.
-
If a ≥ 0, then a = |a|.
If a < 0, then 0 < -a. So a < -a and -a = |a|. Hence a < |a|.
Since either a ≥ 0 or a < 0, then |a| ≥ a.
If a < 0, then 0 < -a. So a < -a and -a = |a|. Hence a < |a|.
Since either a ≥ 0 or a < 0, then |a| ≥ a.
-
the absolute value of a can only be positive where as (a) can either ( -a) or (a)
the absolute value of a is bigger than -a and equal to a
therefore absolute value of a is bigger than or equal to a
the absolute value of a is bigger than -a and equal to a
therefore absolute value of a is bigger than or equal to a
-
The absolute value ensures that a will be a positive number. If a is positive to begin with, then |a|=a. If a was negative to begin with then |a|>a. Hope that helps!