Derivatives - Examples of Derivatives of inverse trigonometric functions

  • Inverse trigonometric functions are the inverse functions of common trigonometric functions.
  • They are denoted by sin^(-1)x (or arcsin(x)), cos^(-1)x (or arccos(x)), and tan^(-1)x (or arctan(x)), among others.
  • Derivatives of inverse trigonometric functions are important in calculus and are derived using differentiation rules.

Derivative of arcsin(x)

  • The derivative of arcsin(x) is given by the formula: d(arcsin(x))/dx = 1 / sqrt(1 - x^2).
  • Example: Find d(arcsin(x))/dx if x = 1/2.
    • Solution: Using the formula, d(arcsin(x))/dx = 1 / sqrt(1 - x^2),
    • d(arcsin(1/2))/dx = 1 / sqrt(1 - (1/2)^2) = 1 / sqrt(1 - 1/4) = 1 / sqrt(3/4) = 2 / sqrt(3).

Derivative of arccos(x)

  • The derivative of arccos(x) is given by the formula: d(arccos(x))/dx = -1 / sqrt(1 - x^2).
  • Example: Find d(arccos(x))/dx if x = 1/3.
    • Solution: Using the formula, d(arccos(x))/dx = -1 / sqrt(1 - x^2),
    • d(arccos(1/3))/dx = -1 / sqrt(1 - (1/3)^2) = -1 / sqrt(1 - 1/9) = -1 / sqrt(8/9) = -3 / sqrt(8).

Derivative of arctan(x)

  • The derivative of arctan(x) is given by the formula: d(arctan(x))/dx = 1 / (1 + x^2).
  • Example: Find d(arctan(x))/dx if x = 2.
    • Solution: Using the formula, d(arctan(x))/dx = 1 / (1 + x^2),
    • d(arctan(2))/dx = 1 / (1 + 2^2) = 1 / (1 + 4) = 1 / 5.

Slide 11

  • Inverse trigonometric functions are used to find the angle whose trigonometric value is known.
  • The main inverse trigonometric functions are: arcsin(x), arccos(x), arctan(x), arcsec(x), arccsc(x), and arccot(x).
  • Each of these inverse trigonometric functions has a specific domain and range.

Slide 12

  • The derivative of inverse trigonometric functions can be derived using differentiation rules.
  • These rules include the chain rule, product rule, quotient rule, and power rule.
  • The derivatives of inverse trigonometric functions have specific formulas that can be used to find their values.

Slide 13

  • The derivative of arccosec(x) is given by the formula: d(arccosec(x))/dx = -1 / (|x| * sqrt(x^2 - 1)).
  • Example: Find d(arccosec(x))/dx if x = 2.
    • Solution: Using the formula, d(arccosec(x))/dx = -1 / (|x| * sqrt(x^2 - 1)),
    • d(arccosec(2))/dx = -1 / (|2| * sqrt(2^2 - 1)) = -1 / (2 * sqrt(4 - 1)) = -1 / (2 * sqrt(3)).

Slide 14

  • The derivative of arccsc(x) is given by the formula: d(arccsc(x))/dx = -1 / (|x| * sqrt(x^2 - 1)).
  • Example: Find d(arccsc(x))/dx if x = 3.
    • Solution: Using the formula, d(arccsc(x))/dx = -1 / (|x| * sqrt(x^2 - 1)),
    • d(arccsc(3))/dx = -1 / (|3| * sqrt(3^2 - 1)) = -1 / (3 * sqrt(9 - 1)) = -1 / (3 * sqrt(8)).

Slide 15

  • The derivative of arccot(x) is given by the formula: d(arccot(x))/dx = -1 / (1 + x^2).
  • Example: Find d(arccot(x))/dx if x = 4.
    • Solution: Using the formula, d(arccot(x))/dx = -1 / (1 + x^2),
    • d(arccot(4))/dx = -1 / (1 + 4^2) = -1 / (1 + 16) = -1 / 17.

Slide 21

  • The derivative of arcsec(x) is given by the formula: d(arcsec(x))/dx = 1 / (|x| * sqrt(x^2 - 1)).
  • Example: Find d(arcsec(x))/dx if x = 1/2.
    • Solution: Using the formula, d(arcsec(x))/dx = 1 / (|x| * sqrt(x^2 - 1)),
    • d(arcsec(1/2))/dx = 1 / (|1/2| * sqrt((1/2)^2 - 1)) = 1 / (1/2 * sqrt(1/4 - 1)) = 1 / (1/2 * sqrt(-3/4)) = 2 / sqrt(-3).

Slide 22

  • The derivative of arccsc(x) is given by the formula: d(arccsc(x))/dx = -1 / (|x| * sqrt(x^2 - 1)).
  • Example: Find d(arccsc(x))/dx if x = 1/3.
    • Solution: Using the formula, d(arccsc(x))/dx = -1 / (|x| * sqrt(x^2 - 1)),
    • d(arccsc(1/3))/dx = -1 / (|1/3| * sqrt((1/3)^2 - 1)) = -1 / (1/3 * sqrt(1/9 - 1)) = -1 / (1/3 * sqrt(-8/9)) = -3 / sqrt(-8).

Slide 23

  • The derivative of arccot(x) is given by the formula: d(arccot(x))/dx = -1 / (1 + x^2).
  • Example: Find d(arccot(x))/dx if x = 1/4.
    • Solution: Using the formula, d(arccot(x))/dx = -1 / (1 + x^2),
    • d(arccot(1/4))/dx = -1 / (1 + (1/4)^2) = -1 / (1 + 1/16) = -1 / (17/16) = -16/17.

Slide 24

  • Inverse trigonometric functions can also be differentiated using the chain rule.
  • The chain rule states that if y = f(g(x)), then dy/dx = f’(g(x)) * g’(x).
  • Example: Find the derivative of y = arcsin(2x + 1).
    • Solution: Let u = 2x + 1. Then, y = arcsin(u).
    • Using the chain rule, dy/du = d(arcsin(u))/du = 1 / sqrt(1 - u^2).
    • Also, du/dx = 2.
    • Therefore, dy/dx = dy/du * du/dx = (1 / sqrt(1 - u^2)) * 2 = 2 / sqrt(1 - (2x + 1)^2).

Slide 25

  • Another differentiation rule used for inverse trigonometric functions is the power rule.
  • The power rule states that if y = x^n, then dy/dx = nx^(n-1).
  • Example: Find the derivative of y = arccos(x^3).
    • Solution: Let u = x^3. Then, y = arccos(u).
    • Using the chain rule, dy/du = d(arccos(u))/du = -1 / sqrt(1 - u^2).
    • Also, du/dx = 3x^2.
    • Therefore, dy/dx = dy/du * du/dx = (-1 / sqrt(1 - u^2)) * 3x^2 = -3x^2 / sqrt(1 - x^6).

Slide 26

  • The product rule is another differentiation rule that can be used for inverse trigonometric functions.
  • The product rule states that if y = f(x)g(x), then dy/dx = f’(x)g(x) + f(x)g’(x).
  • Example: Find the derivative of y = tan(x) arcsin(x).
    • Solution: Let u = tan(x) and v = arcsin(x).
    • Using the product rule, dy/dx = u’v + uv'.
    • u’ = sec^2(x) and v’ = 1 / sqrt(1 - x^2).
    • Therefore, dy/dx = sec^2(x) * arcsin(x) + tan(x) * (1 / sqrt(1 - x^2)).

Slide 27

  • The quotient rule is another differentiation rule used for inverse trigonometric functions.
  • The quotient rule states that if y = f(x) / g(x), then dy/dx = (f’(x)g(x) - f(x)g’(x)) / (g(x))^2.
  • Example: Find the derivative of y = sin(x) / arccos(x).
    • Solution: Let u = sin(x) and v = arccos(x).
    • Using the quotient rule, dy/dx = (u’v - uv’) / (v)^2.
    • u’ = cos(x) and v’ = -1 / sqrt(1 - x^2).
    • Therefore, dy/dx = (cos(x) * arccos(x) - sin(x) * (-1 / sqrt(1 - x^2))) / (arccos(x))^2.

Slide 28

  • The derivatives of inverse trigonometric functions are essential in solving various calculus problems.
  • These derivatives can be used to find tangents, rates of change, and limits involving inverse trigonometric functions.
  • Understanding the derivatives of inverse trigonometric functions is crucial for success in higher-level calculus courses.
  • It is important to practice differentiating inverse trigonometric functions to become comfortable with the formulas and rules.
  • Remember to apply the appropriate differentiation rule, whether it be the chain rule, product rule, quotient rule, or power rule.

Slide 29

  • Inverse trigonometric functions are widely used in calculus, physics, engineering, and other disciplines.
  • They play a key role in solving various mathematical problems involving angles and trigonometric relationships.
  • By understanding their derivatives, we can solve more complex problems and gain deeper insights into the behavior of these functions.
  • It is always important to double-check your calculations and interpretations of inverse trigonometric functions and their derivatives.
  • Don’t hesitate to seek additional resources and guidance if you encounter difficulties or have further questions.

Slide 30

  • In conclusion, the derivatives of inverse trigonometric functions are a fundamental concept in calculus.
  • By knowing the derivatives of arcsin(x), arccos(x), and arctan(x), as well as other inverse trigonometric functions, we can solve a wide range of mathematical problems.
  • Remember the specific formulas for each derivative and how to apply differentiation rules like the chain rule, product rule, quotient rule, and power rule.
  • Practice applying these concepts with different examples to develop a strong understanding and proficiency in solving calculus problems involving inverse trigonometric functions.
  • Keep exploring and applying your knowledge to further advance your skills in calculus.+