What is the Value of (p+q-2t) and (p^2+q^2-2t^2) in an Equation with Degree 3?

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The discussion centers on determining the values of (p+q-2t) and (p^2+q^2-2t^2) for the cubic equation 8x^3 + 4cx^2 + 2(b-3)x + (a-2c) = 0, where p, q, and t are the roots. The coefficients of the polynomial can be expressed in terms of the roots using Vieta's formulas: p+q+t = c/2, pq+pt+qt = (b-3)/4, and pqt = (2c-a)/8. By rewriting the polynomial as 8(x-p)(x-q)(x-t) and expanding, one can derive the necessary expressions for (p+q-2t) and (p^2+q^2-2t^2) based on these relationships.

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I have an equation similar:
8x^3+4cx^2+2(b-3)x+(a-2c)=0
a, b, c are real number.
if p, q , t be roots.
What can say about (p+q-2t) and (p^2+ q^2-2t^2)?
Please help me??
Thanks so much.
 
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hint: write your polynomial as 8(x-p)(x-q)(x-t) and multiply it out, then compare coefficients.
 
I know
p+q+t=c/2
pq+pt+qt=(b-3)/4
pqt=(2c-a)/8
but I need value for
(p+q-2t)??
(p^2+ q^2-2t^2)?
Please help me??
 

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