Characteristic Equation Roots

Problem

Find the roots of the characteristic equation lambda^2 + b*lambda + c = 0.

Return both real roots sorted in ascending order. If the discriminant b^2 - 4*c is negative, return an empty list. A repeated root is returned twice.

Hint

Use the quadratic formula; the discriminant decides how many real roots exist.

case 1

in: [-5,6]

expected: [2,3]

case 2

in: [0,1]

expected: []

case 3

in: [2,1]

expected: [-1,-1]

case 4

in: [-4,4]

expected: [2,2]

case 5

in: [3,2]

expected: [-2,-1]

Starter codePython

def char_roots(b, c):
    # Your code here
    pass

5 test cases · run your code against them in the editor