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α and β are the roots of the equ. ax2+bx+c = 0 and α4, β4 are the roots of the equation lx2+ mx +n = 0 (α,β are real and distinct) . Let f(x) = a2lx2 - 4aclx - 2c2l +a2m = 0 then One root of the f(x) = 0 is i. 82b2ii. b2a2iii. b/aiv. a/b

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Dear student


NOTE: If px2+qx+r is a quadratic equations.Then Sum of roots=-Coeff. of xCoeff. of x2=-qpand product of roots=Constant termCoeff. of x2=rpSince α and β are the roots of ax2+bx+c=0.Then α+β=-baand αβ=ca ....(1)Also, α4 and β4 are the roots of lx2+mx+n=0Then α4+β4=-ml ...(2)and α4β4=nlNow, Consider,f(x)=a2lx2-4aclx+2c2l+a2m=0Then x=4acl±4acl2-4a2l2c2l+a2m2a2lx=4acl±16a2c2l2-8a2c2l2-4a4lm2a2lx=4acl±8a2c2l2-4a4lm2a2lx=4acl±2al2c2-a2ml2a2lx=2ca±1a2c2a2a2-a2mlx=2ca±aa2c2a2-mlx=2αβ±2α2β2+α4+β4 using 1 and 2x=2αβ±α2+β22x=2αβ±α2+β2
x=2αβ±α+β2-2αβ x+y2=x2+y2+2xyx=2αβ+α+β2-2αβ or x=2αβ-α+β2-2αβx=α+β2 or x=4αβ-α+β2x=b2a2 or x=4ca-b2a2x=b2a2 or x=4ac-b2a2So, one of the root of f(x)=0 is b2a2

Regards

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