C-11-Q045mediumsingle_mcqab=cd\dfrac{a}{b}=\dfrac{c}{d}ba=dc হলে a−bb=?\dfrac{a-b}{b} = ?ba−b=?ac−dd\dfrac{c-d}{d}dc−dbc+dd\dfrac{c+d}{d}dc+dcc−da\dfrac{c-d}{a}ac−ddc+da\dfrac{c+d}{a}ac+d