function x = bisection(a, b, n)
c = f(a);
d = f(b);
if c * d > 0
error('The function has same sign on both the sides')
end
for i = 1 : n
x = (a + b) / 2;
if f(a) * f(x) < 0
b = x;
elseif f(b) * f(x) < 0
a = x;
end
end
end