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Python

Posted by Amaka Nnorom
Amaka Nnorom
215 Points

writing a program for math calculation

A typical quadratic equation is of the form ax² + bx + c = 0 where 'a', 'b' and 'c' are constants. 'a' can never be equal to zero. 'x' is a variable (the root of the quadratic equation). A quadratic equation has 2 roots and the formula for calculating the roots of a quadratic equation is given in the image below. Given the quadratic equation 2x² + 5x + 3 then, 'a' = 2, 'b' = 5 and 'c' = 3. Write a python program to calculate the roots of a quadratic equation for any combination of values for 'a', 'b', 'c' and display the roots as output. HINT: You can use three input functions to receive the values of a, b and c from the user. Also, write an expression for the quadratic formula. Do not use the python math module. Captionless Image

1 Answer

jhon white
jhon white
20,006 Points
jhon white
jhon white
20,006 Points 
def sqrt(n):
    return n**(1/2)


print("Quadratic function : (a * x^2) + b*x + c")
a = float(input("a: "))
b = float(input("b: "))
c = float(input("c: "))

r = b**2 - 4*a*c

if r > 0:
    num_roots = 2
    x1 = (((-b) + sqrt(r))/(2*a))     
    x2 = (((-b) - sqrt(r))/(2*a))
    print("There are 2 roots: %.2f and %.2f" %(x1,x2))
elif r == 0:
    num_roots = 1
    x = (-b) / 2*a
    print("There is one root: ", x)
else:
    num_roots = 0
    print("No roots, discriminant < 0.")
    exit()