C-11-Q033mediumsingle_mcqa:b=c:da:b=c:da:b=c:d হলে যোজন-বিয়োজন প্রয়োগে —aa+ba−b=c+dc−d\dfrac{a+b}{a-b} = \dfrac{c+d}{c-d}a−ba+b=c−dc+dba−ba+b=c+dc−d\dfrac{a-b}{a+b} = \dfrac{c+d}{c-d}a+ba−b=c−dc+dca+bc+d=a−bc−d\dfrac{a+b}{c+d} = \dfrac{a-b}{c-d}c+da+b=c−da−bdabcd=1\dfrac{ab}{cd} = 1cdab=1