70 likes | 372 Views
AP Calculus BC – 4.5: Linearization and Newton’s Method - 2. Goals : Find linearizations and use Newton’s method to approximate the zeros of a function. Estimate the change in a function using differentials. Linearization: As long as it’s close, it’s close.
E N D
AP Calculus BC – 4.5: Linearization and Newton’s Method - 2 Goals: Find linearizations and use Newton’s method to approximate the zeros of a function. Estimate the change in a function using differentials.
Linearization: As long as it’s close, it’s close. If f is differentiable at x = a, then the approximating function is the linearization of f at a. The approximation f(x)≈ L(x) is the standard linear approximation of f at a. The point x = a is the center of the approximation.
Newton’s Method (Newton-Raphson Method): Newton’s Method is a numerical technique for approximating a zero of a function with zeros of its linearizations. Procedure: 1.Guess a first approximation to a solution of the equation f(X) = 0. A graph of y = f(X) may help. 2. Iterate. Use the first approximation to get a second, and so on, using:
Differentials: Differentials: Let y = f(x) be a differentiable function. The differential dx is an independent variable. The differential dy is dy = f’(x) dx. Differential Estimate of Change: Let f(x) be differentiable at x = a. The approximate change in the value of f when x changes from a to a + dx is df = f’(a)dx.
Absolute, Relative, and Percentage Change: As we move from a to a nearby point a+dx: True Estimated Absolute Change Relative Change Percentage Change
Assignments and Notes: • HW 4.5A: #3, 5-9, 11, 14, 15, 18. • HW 4.5B: #19, 22, 25, 27, 30, 33, 36, 39, 44, 50, 51. Look at #52. • Test next Thursday.