# BISECTION METHOD
# Aim - TO IMPLEMENT BISECTION METHOD USING JUPYTER NOTEBOOK
from math import log, ceil
x=0

def bisec(x):
    func = (x**3)-(4*x)-9
    return func

a=2
b=3
err = 0.02
c1=(a+b)/2
print(c1)
c2=0
n= (log(b-a)-log(err))/log(2)
print(n)
i=0
while i<ceil(n):
#     print("c1 b4= ",c1)
#     print("c2 b4= ",c2)
#     print("a b4 = ",a)
#     print("b b4 = ",b)
    if bisec(b)*bisec(c1)<0:
        c2=c1
        a=c1
        print("a becomes c")

    elif bisec(a)*bisec(c1)<0:
        c2=c1
        b=c1
        print("b becomes a")
    print("c1 af= ",c1)
#     print("c2 af= ",c2)
#     print("a af = ",a)
#     print("b af = ",b)
    print("i = ",i)
    c1=(a+b)/2
    i+=1
print("Root is - ",c1)