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Question
hello this question is from ordered in realnumber.
if 'a' and 'b' two real number
if a > 0
then -a < 0
proof:-
a > 0
a-a>0-a
0>-a
if a < 0
then -a > 0
proof-
a < 0
a-a<0-a
0<-a
could you please explain the second proof.how -a can be greater than 0.please explain it
Say a = -56, then -a = 56. It is seen that 56 > 0.
If x were the right positive number, we would have a = -x.
Multiply by -1 and get -a = x. Since x is positive,
-a has the same value, so -a is positive.
Another way: if a is a negatvie number, the negative of a negative is a positive.
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