Let f(x)=x4−ax2+b and g(x)=x2−3x+2=(x−1)(x−2) ∵g(x) is a factor of f(x) ⇒(x−1) and (x−2) are factors of f(x) ∴f(1)=0 and f(2)=0 [by factor theorem] ⇒1−a+b=0 and 16−4a+b=0 Solving above equations, we have a=5,b=4 Equation whose roots are ' a ' and ' b ' is x2−(a+b)x+ab=0 or x2−9x+20=0