Theory of equations
Let alpha , beta , gamma be the roots of (x-a)(x-b)(x-c) =d , (d not equal to 0) , then the roots of the equation \[(x-\alpha)(x-\beta)(x-\gamma) +d =0\] are?
\[x ^{3} + (ab+ac+bc)x -[x ^{2}(a+b+c)] -abc =d \]
@ganeshie8
x^3 - x^2(a+b+c)+x(ab+bc+ca) -abc -d = 0 α+β+γ =-( a+b+c ) αβ+βγ+γβ = ab+bc +ca αβγ= -(abc+d) or abc = -(d + αβγ)
Since \(\alpha, \beta, \gamma \) are roots of first equation : \( (x-a)(x-b)(x-c)-d = (x-\alpha)(x-\beta)(x-\gamma)\) \( \implies (x-a)(x-b)(x-c) = (x-\alpha)(x-\beta)(x-\gamma)+ d\) \(\implies \) roots of second equation area \(a, b, c\)
the roots of the required equaion is a,b,c
Yes the roots are indeed a,b,c Thank you both of you ! I got it
yw
I got what what you did @matricked but didn't get hpow you arrvived at the conclusion that a,b,c are the roots
I got using the realtion between the roots and the coefficients..
I mean i got how u did x^3 - x^2(a+b+c)+x(ab+bc+ca) -abc -d = 0 α+β+γ =-( a+b+c ) αβ+βγ+γβ = ab+bc +ca αβγ= -(abc+d) or abc = -(d + αβγ) But didn't how u arrived at the conclusion
first expand (x−α)(x−β)(x−γ)+d =0 ( a+b+c ) =-(α+β+γ ) ab+bc +ca = αβ+βγ+γβ abc = -(d + αβγ)
Ah , i get it thanks
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