Solve the given quadratic equation that involves sum and product

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The discussion focuses on solving a quadratic equation using the relationships between the sum and product of its roots, denoted as α and β. Part a derives a formula involving the roots, leading to the expression (c-1)² + b². In part b, a quadratic equation is formulated with coefficients derived from the roots and their relationships. Participants confirm the correctness of the approach and seek alternative methods for solving the problem. Overall, the thread emphasizes the mathematical derivation and verification of the quadratic equation based on the given parameters.
chwala
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Homework Statement
See attached below;
Relevant Equations
sum/product
1644621814964.png


For part a,
We have ##α+β=b## and ##αβ =c##. It follows that,
##(α^2 + 1)(β^2+1)=α^2β^2+α^2+β^2+1)##
=##α^2β^2+(α+β)^2-2αβ +1##
=##c^2+b^2-2c+1##
=##c^2-2c+1+b^2##
=##(c-1)^2+b^2##

For part b,..we shall have
##x^2- \dfrac{α+β+α^2β +αβ^2}{(α^2 + 1)(β^2+1)}## ##x## +##\dfrac {αβ}{(α^2 + 1)(β^2+1)}##
##x^2-\dfrac{α+β+αβ(β +α)}{(α^2 + 1)(β^2+1)}####x##+##\dfrac {αβ}{(α^2 + 1)(β^2+1)}##
##x^2-\dfrac{b(1+c)}{(c-1)^2+b^2}####x##+##\dfrac {c}{(c-1)^2+b^2}##

Is this correct?( i do not have the solutions)...i would appreciate different ways of attempting the problem. Cheers.
 
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It seems all right.
 
The working out suggests first equating ## \sqrt{i} = x + iy ## and suggests that squaring and equating real and imaginary parts of both sides results in ## \sqrt{i} = \pm (1+i)/ \sqrt{2} ## Squaring both sides results in: $$ i = (x + iy)^2 $$ $$ i = x^2 + 2ixy -y^2 $$ equating real parts gives $$ x^2 - y^2 = 0 $$ $$ (x+y)(x-y) = 0 $$ $$ x = \pm y $$ equating imaginary parts gives: $$ i = 2ixy $$ $$ 2xy = 1 $$ I'm not really sure how to proceed from here.