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Direct integration initial value problems

#028

Problem

y=5x42x+7,y(0)=1y' = 5x^4 - 2x + 7,\quad y(0)=-1Open Model Lab

Classification

  • power rule
  • initial condition

Method

  • direct integration
  • initial value problem

Solution

y=x5x2+7x1y = x^5 - x^2 + 7x - 1

Simulation & Code

Computational workSimulation
Graph visualization for entry #028
Download .py file
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

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Takeaway & 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.