Question

in inequalities.
when the sign of +ve and -ve must be exchange.
and when the inequalities sign must reversed.?

Answer 1

when you are multiplying by negative number

Answer 2

for example
3<5
if you multiply -1, following inequality no longer hold
-3 < -5
so we flip
-3>-5

Answer 3

0h.. ok.. multiply.. how about dividing? it is the same?

Answer 4

same. actually dividing is just a multiplication with inverse
4/2 = 4 * 1/2

Answer 5

ok i got it.. thenks..