OFFSET
1,1
COMMENTS
FORMULA
greatest root: -(3/2) + sqrt(19/3) cos(1/3 arctan((4 sqrt(427/3))/3))
middle root: -(3/2) - 1/2 sqrt(19/3) cos(1/3 arctan((4 sqrt(427/3))/3)) + 1/2 sqrt(19) sin(1/3 arctan((4 sqrt(427/3))/3))
least root: -(3/2) - 1/2 sqrt(19/3) cos(1/3 arctan((4 sqrt(427/3))/3)) - 1/2 sqrt(19) sin(1/3 arctan((4 sqrt(427/3))/3))
EXAMPLE
greatest root: 0.70530340009105630377...
middle root: -1.5526623262135260618...
least root: -3.6526410738775302420...
MATHEMATICA
PROG
(PARI) solve(x=-4, -3, 2*x^3 + 9*x^2 + 4*x - 8) \\ Michel Marcus, Aug 11 2018
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Aug 09 2018
STATUS
approved