Core Concepts of Calculus Explained

Aug 31, 2024

Fundamentals of Calculus

Three Areas of Calculus

  1. Limits

    • Evaluate a function as it approaches a certain value.
    • Useful for functions that are undefined at a particular point.
  2. Derivatives

    • Determine the slope of a function at a particular value.
    • Represented as f'(x).
    • Useful for calculating rates of change.
  3. Integration

    • Opposite process of differentiation.
    • Determine the area under a curve.
    • Calculated as the integral of f'(x), which is f(x).

Limits

  • Example: f(x) = (x² - 4) / (x - 2)
    • Evaluating at x = 2 gives 0/0, indeterminate.
    • Use limits to see behavior as x approaches 2.
    • Factor and simplify to find the limit = 4.

Derivatives

  • Definition: Provides slope of tangent line to the curve.
  • Power Rule: Derivative of xⁿ is n * xⁿ⁻¹.
    • Example: Derivative of x² is 2x.
  • Tangent vs. Secant Line
    • Tangent: touches at one point, slope = derivative.
    • Secant: touches at two points, slope calculated traditionally.
  • Example: f(x) = x³
    • f'(x) = 3x²

    • Slope at x = 2 is 12.

Calculating Derivatives via Limits

  • Use limits to find slope: limit as x approaches a value.
  • Factor and simplify expressions to use limits.
  • Differentiation tells rate of change.

Integration

  • Process of finding the anti-derivative.
    • Example: Integral of 4x³ gives x⁴ (plus constant).
  • Used to find accumulation over time.
  • Definite vs. Indefinite Integrals
    • Definite: Has limits, gives numerical result.
    • Indefinite: No limits, gives function.

Example Problem

  • Function for water in tank: A(t) = 0.01t² + 0.5t + 100
  • Calculate amount at t = 0, 9, 10, 11, 20.
    • Use integration for accumulation over time.

Rates of Change

  • Derivative tells how fast water changes in tank.
  • Integrals accumulate water over time.

Graphical Representation

  • Integration finds area under curve.
  • Divide region into geometric shapes (rectangle, triangle) to calculate area.

Summary

  • Limits: Evaluate function behavior as it approaches a value.
  • Derivatives: Calculate instantaneous rate of change.
  • Integration: Determine accumulation over time by finding area under the curve.

Conclusion

  • These concepts are fundamental in calculus.
  • Recommended to check additional resources for practice and deeper understanding.