Question

help

Answer 1

do you know formula of discriminant ?

Answer 2

in function of discriminant

D > 0

D = 0

D < 0

there are 3 cases of roots (solutions) for a quadratic

Answer 3

degree of f(x)=number of solutions.
count the number of changes of sign in f(x)
it gives number of positive roots.
count the number of changes of sign in f(-x)
it gives number of negative roots.
irrational and complex roots always occur in pairs.