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24
Equation with degree 4
Equation with degree 4
Source:
September 5, 2010
algebra
polynomial
Vieta
algebra unsolved
Problem Statement
Prove that if the equation
x
4
+
a
x
3
+
b
x
+
c
=
0
x^4 + ax^3 + bx + c = 0
x
4
+
a
x
3
+
b
x
+
c
=
0
has all its roots real, then
a
b
≤
0.
ab \leq 0.
ab
≤
0.
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