in a triangle abc
let /_b > /_c
we need to prove ac> ab
assumption - ac not greater than ab
so, ac = ab (or) ac<ab
(i) ac is not equal to ab as
/_b is not equal to /_c
(ii) ac is not less than ab
/_b is not less than /_c
as the statement "ac = ab (or) ac<ab " is wrong, the assumption "ac not greater than ab" is also wrong
hence, ac> ab
