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Essential Derivative Rules in Calculus

Sep 24, 2024

Review of Derivative Rules in Calculus

Derivative Rules Overview

  • Power Rule
  • Constant Multiple Rule
  • Sum Rule
  • Difference Rule
  • Product Rule
  • Quotient Rule
  • Chain Rule

Examples and Application of Derivative Rules

Example 1: Using Power Rule and Constant Multiple Rule

  • Function: (-x^5 + 5x^3 + \sqrt[3]{x^2})
  • Rewrite (\sqrt[3]{x^2}) as (x^{2/3})
  • Apply Power Rule:
    • Derivative of (-x^5) is (-5x^4)
    • Derivative of (5x^3) is (15x^2)
    • Derivative of (x^{2/3}) is (\frac{2}{3}x^{-1/3})
  • Final derivative: (-5x^4 + 15x^2 + \frac{2}{3x^{1/3}})

Example 2: Using Product Rule

  • If (f(x) = 11x + 2) and (g(x) = -5 + 3x^2)
  • Product Rule: (f'(x)g(x) + g'(x)f(x))
  • Derivative: (99x^2 + 12x - 55)

Example 3: Using Quotient Rule

  • Derivative of a quotient ((f/g)' = (g'f - fg')/g^2)
  • Function: ((x^2 - 4)/(2x + 5))
  • Derivative: (\frac{2x^2 + 10x + 8}{(2x + 5)^2})

Example 4: Using Chain Rule

  • Function: ((3x - 2)^2)
  • Chain Rule: Differentiate outer function, multiply by derivative of inner function
  • Derivative: (6(3x - 2))

Example 5: Combination of Chain Rule and Product Rule

  • Use product rule with functions that require chain rule
  • Simplify using common factors
  • Example: (2x - 3)^3 \times (3x - 1)^2)
  • Final Derivative: (6(2x - 3)^2(3x - 1)(5x - 4))

Example 6: Combination of Quotient Rule and Chain Rule

  • Function: (\frac{8x^3}{\sqrt{3x - 2}})
  • Factor out common terms to simplify
  • Final derivative in simplified form

Application: Finding Equation of Tangent Line

Example: Tangent Line at a Point

  • Function: (y = \frac{2x}{(x + 1)^6})
  • Find tangent at (x = 1)
  • Calculate (y(1) = 1)
  • Use derivative to find slope (m = 3)
  • Equation of tangent line: (y = 3x - 2)

Conclusion

  • Review of main derivative rules from high school calculus
  • Importance of understanding and practicing each rule
  • Refer to individual topic videos for more detailed explanations