Title: Now%20that%20you
1Now that youve found a polynomial to approximate
your function, how good is your polynomial?
Find the 6th degree Maclaurin polynomial for
For what values of x does this polynomial best
follow the curve? Where does the polynomial
poorly follow the curve?
2What are the limitations of graphically analyzing
a Taylor polynomial?
3Suppose that a function f(x) has derivatives at x
0 given by the formula
Write the first few terms of the Taylor series
centered at x 0 for this function.
4Write the 4th degree Taylor polynomial for f
centered at x 0.
Estimate the error in using the 4th degree
polynomial to approximate f(0.2).
5Error Bounds for ALTERNATING Series
6Example
Write the 4th degree Maclaurin polynomial for
Show that this polynomial approximates cos(.9) to
better than 1 part in 1000.
7Example
Consider the power series
What is the maximum error in truncating the
function after the 4th term on the interval -.5 lt
x lt .5?
8Example
Suppose that f is a function such that f(2)3 and
Write the 3rd degree Taylor polynomial for f
centered at x 2.
Estimate f(2.1). What is the maximum difference
between your estimate and the actual value of
f(2.1)?
9What is the 4th degree Maclaurin polynomial for
?
Using the polynomial, estimate y(.2). How good
is your estimate? Why we cant we use our usual
method to estimate the error?
10Taylors Theorem
The difference between a function at x and its
nth degree Taylor polynomial centered a is
for some c between x and a.
11Taylors Theorem is an existence theorem. What
does that mean?
What other existence theorems have we seen in
Calculus?
12Recall our 4th degree polynomial for
and our estimate for y(.2).
Use Taylors Theorem to estimate the difference
between our estimate and the true value of y(.2).
13Lagrange Error Bound
Choose M to be at least as big as the maximum
value of the n1 derivative on the interval x to
a.
14Example
Write the 3rd degree Taylor polynomial, P(x), for
centered at x 0.
Estimate the error in using P(.2) to approximate
.