Find cube root of the form ax^3 + bx^2 + cx + d=0

Find cube root of the form ax^3 + bx^2 + cx + d=0

cub_root_select(a, b, c, d, q_1, q_2)

Arguments

a

parameter 1 in cubic equation

b

parameter 2 in cubic equation

c

parameter 3 in cubic equation

d

parameter 4 in cubic equation

q_1

lower quantile to bound the root

q_2

upper quantile to bound the root