# File: quad-c.py
# Compute the roots of a quadratic equation (user enters coefficients)
#
# Matt Bishop, ECS 10, Spring 2014
#
import math # load up the math functions
#
# compute the discriminant
# parameters: a, b, c: coefficients
# returns: b^2 -4ac
#
def discrim(a, b, c):
return b * b - 4 * a * c
#
# the main routine
#
def main():
# read in the coefficients
try:
a = float(raw_input("Enter x2 coefficient: "))
b = float(raw_input("Enter x coefficient: "))
c = float(raw_input("Enter 1 coefficient: "))
except:
print "You must enter real numbers for coefficients!!!"
return
# get the discriminant
d = discrim(a, b, c)
# compute the roots
try:
# get the first root
r1 = (-b + math.sqrt(d)) / (2*a)
# get the second root
r2 = (-b - math.sqrt(d)) / (2*a)
except:
print "The roots of this polynomial are complex numbers"
return
# print them out
print "The roots are", r1, "and", r2
# go!
main()