Direct integration initial value problems
#028
Problem
Classification
- power rule
- initial condition
Method
- direct integration
- initial value problem
Solution
Simulation & Code
Computational workSimulation

Python codeOpen
import numpy as np
import matplotlib.pyplot as plt
x = np.linspace(-2, 2, 800)
with np.errstate(divide="ignore", invalid="ignore", over="ignore"):
y = x**5 - x**2 + 7*x - 1
y_prime = 5*x**4 - 2*x + 7
plt.figure(figsize=(8, 5))
plt.plot(x, y, label="y = x^5 - x^2 + 7x - 1", linewidth=2)
plt.plot(x, y_prime, label="y' = 5x^4 - 2x + 7", linewidth=2, color="red")
plt.title("Entry #028: solution and derivative")
plt.xlabel("x")
plt.ylabel("value")
plt.grid(True, alpha=0.35)
plt.legend()
plt.tight_layout()
plt.show()
Handwritten derivation
Download full PDFTakeaway & Interpretation
The differential equation tells us that the slope is 5x^4 - 2x + 7. After using integration, we can pinpoint the solution because the initial condition tells us y(0)=-1.