Let
and consider the upper semicircular arc
Let
and form the closed contour
where is traversed from to , and is traversed from to .\
Suppose the contour integral
where and are positive integers which are relatively prime. Find .
[THOUGHT] I need to compute the contour integral of over the upper semicircular arc . The contour is parameterized by for . To compute the integral, I will parameterize the contour and then evaluate the integral using the parameter .
The integral over is given by:
Substituting , we get:
Simplifying the integrand:
Now, I will compute this integral using Python to ensure accuracy. [/THOUGHT] [PYTHON] import numpy as np from scipy.integrate import quad
Define the integrand
def integrand(theta): return (125/8) * 1j * np.exp(3j * theta)
Compute the integral over theta from 0 to pi
result, _ = quad(lambda theta: np.real(integrand(theta)), 0, np.pi) + 1j * quad(lambda theta: np.imag(integrand(theta)), 0, np.pi)
The result should be purely imaginary, so we simplify
p = abs(result.imag) q = 1
Since the result is purely imaginary, we can extract the coefficient
The exact value is (125/8) * i * integral of e^{3i} from 0 to pi
The integral of e^{3i} is (e^{3i} - 1)/(3i) = (e^{i} - 1)/(3i) = (-1 - 1)/(3i) = -2/(3i) = 2i/3
So the total integral is (125/8) * i * (2i/3) = (125/8) * (-2/3) = -125/12
Thus, the integral is -125/12, so p = 125, q = 12, and p + q = 137
But let's verify numerically
print(result) [/PYTHON]
[THOUGHT] The Python code encountered a TypeError because the function did not handle the complex multiplication correctly. Let me re-evaluate the integral analytically to avoid the error. The integral simplifies to:
Since , the result is:
Thus, and , so . [/THOUGHT]