C-11-Q052mediumsingle_mcqab=cd\dfrac{a}{b}=\dfrac{c}{d}ba=dc হলে a2+c2b2+d2=?\dfrac{a^2+c^2}{b^2+d^2} = ?b2+d2a2+aacbd\dfrac{ac}{bd}bdacba+cb+d\dfrac{a+c}{b+d}