Categories: All - tangent - chain - differentiation - derivative

by David Kedrowski 14 years ago

278

MAT.126 2.4-2.5

Implicit differentiation is a technique used to find the derivative of functions that are defined implicitly rather than explicitly. The process involves differentiating both sides of the equation with respect to x and then solving for dy/

MAT.126 2.4-2.5

MAT.126 2.4-2.5

2.5 Implicit Differentiation

Use implicit differentiation to find the derivative of a function

  • Differentiate both sides of the equation with respect to x.
  • Collect all terms involving dy/dx on the left side of the equation and move all other terms to the right side of the equation.
  • Factor dy/dx out of the left side of the equation.
  • Solve for dy/dx.
  • Tangent Line to an Implicit Graph
    Higher-Order Implicit Derivatives
    Explicit Domains for Implicit Functions
    Slope of an Implicit Graph
    Graphing Implicit Relations
    Process
    Chain Rule

    To differentiate an implicitly defined function one must use the chain rule on all terms involving y.

    d dy

    ---[ f(y) ] = f'(y) ----

    dx dx

    Distinguish between functions written in implicit form and explicit form

    Explicit: y = f(x)

    Implicit: y and f(x) are mixed together

    2.4 The Chain Rule

    Summary of Differentiation Rules

    p. 136

    Find the derivative of a trigonometric function using the Chain Rule
    Tangent Lines
    Repeated Application of the Chain Rule
    Parentheses
    Simplify the derivative of a function using algebra
    Powers
    Quotients
    Factoring Out Least Powers
    Find the derivative of a function using the General Power Rule

    If y = [u(x)]^n, where u is a differentiable function of x and n is a rational number, then

    dy du

    --- = n[u(x)]^{n-1} ---

    dx dx

    or, equivalently

    d

    ---[u^n] = n*u^{n-1} u'

    dx

    Quotients with Constant Numerators

    d

    ---[ sin u ] = (cos u) u'

    dx

    d

    ---[ cos u ] = -(sin u) u'

    dx

    d

    ---[ tan u ] = (sec^2 u) u'

    dx

    d

    ---[ cot u ] = -(csc^2 u) u'

    dx

    d

    ---[ sec u ] = (sec u tan u) u'

    dx

    d

    ---[ csc u ] = -(csc u cot u) u'

    dx

    Radicals
    Find the derivative of a composite function using the Chain Rule

    If y = f(u) is a differentiable function of u and u = g(x) is a differentiable function of x, then y = f(g(x)) is a differentiable function of x and

    dy dy du

    --- = --- * ---

    dx du dx

    or, equivalently

    d

    ---[ f(g(x)) ] = f'(g(x)) g'(x)

    dx

    Decomposition