In the following, remember that f(n)(x) represents the nth
derivative of f, and assume s > 0.
(a) By giving an appropriately diverse selection of samples
functions f, explain why it is reasonable to assume that for “most”
functions f, there is some value s for which lim x→∞ f(x)e−sx = 0.
(In other words, pretend you’re the teacher of a differential
equations class trying to convince the class that this assumption
is a reasonable one! Don’t just claim the limit is 0; show that the
limit is 0 for your chosen example functions) (b) Suppose lim x→∞
f(x)e−sx = 0. Find lim x→∞ f(n)(x)e−sx. Suggestion: Visit the
l’Hˆopital. (c) Suppose lim x→∞ f(n)(x)e−sx = 0. Find lim x→∞
f(x)e−sx. Suggestion: Your intuition should suggest it’s 0. What if
it isn’t?
In the following, remember that f(n)(x) represents the nth derivative of f, and assume s >...
n If f(x) = Σ a;x' is a polynomial in R[x], recall the derivative f'(x) is a polynomial as well i=0 (we'll talk more about the fact that derivatives are linear, in chapter 3). Recall I write R[x]n for the polynomials of degree < N. Let P(x) = aixº be degree N, N i=0 a.k.a. assume an # 0. Show that the derivatives P(x), P'(x), ...,P(N)(x) form a basis of R[x]n (where p(N) means the Nth derivative of P).
2. Sketch the graph of the following functions and find the values of x for which lim f(x) does not exist. b)/(x) = 1, x = 0 f(x)- 5, x=3 c) x2 x>1 2x, x> 3 d) f(x)-v e) (x)- [2x 1- sin x Discuss the continuity of the functions given in problem #2 above. Also, determine (using the limit concept) if the discontinuities of these functions are removable or nonremovable 3. Find the value of the constant k (using...
Real analysis 10 11 12 13 please (r 2 4.1 Limit of Function 129 se f: E → R, p is a limit point of E, and limf(x)-L. Prove that lim)ILI. h If, in addition, )o for all x E E, prove that lim b. Prove that lim (f(x))"-L" for each n E N. ethe limit theorems, examples, and previous exercises to find each of the following limits. State which theo- rems, examples, or exercises are used in each case....
Assume lim f(x) = 8 and lim g(x)=6. Compute the following limit and state the limit laws used to justify the computation. limf(x)g(x) + 16 limx19(x) + 16 = (Simplify your answer.) Select each limit law used to justify the computation. D A Constant multiple B. Quotient C. Power D. Root E Product F. Difference O Sum
Let Coo denote the set of smooth functions, ie, functions f : R → R whose nth derivative exists, for all n. Recall that this is a vector space, where "vectors" of Coo are function:s like f(t) = sin(t) or f(t) = te, or polynomials like f(t)-t2-2, or constant functions like f(t) = 5, and more The set of smooth functions f (t) which satisfy the differential equation f"(t) +2f (t) -0 for all t, is the same as the...
(Limit of functions) Let f : 2-» C be a function, and assume that D(a, r) C Q. We say that lim f(z) L Ď(a, 6) we have |f(z) Ll < e. if for any e > 0 there exists 6 > 0, such that for any z e (a) State the negation of the assertion "lim^-,a f(z) = L". (b) Show that lim- f(z) L if and only if for any sequence zn -» a, with zn a for...
We have the following Limit Comparison Test for improper integrals: Theorem. Suppose f(x), g(x) are two positive, decreasing functions on all x > 1, and that lim f(x) =c70 x+oo g(x) Then, roo 5° f(x) dx < oo if and only if ſº g(x) dx < 00 J1 (a) Using appropriate convergence tests for series, prove the Limit Comparison Test for improper integrals. (Hint: Define two sequences an = f(n), bn = g(n). What can you say about the limit...
Just the ones without answers plz 3x Consider the hyperbola f(x) = The numerator is dominated by 3x and the numerator is dominated by x, so we can easily convince ourselves that the limit of this function as x goes to infinity is L = lim f(x) =3 Now we prove this using the formal definition of a limit. Given any e 0 assume x> M.Since M can be large we also assume that M> 2 So: Step 1. Using...
2nt The Maclaurin series of f(x) is Š S 19 +1. The Maclaurin serie N=0 (a) What is the open interval of convergence of this Maclaurin series? O(-00,00) O(-1,1) O(-,) O(-2,2) 0 (0,1) (b) Evaluate the limit w lim x0 f(x) - x3 (Hint: It helps to write down the first few terms of the series.)
Find the following trigonometric limit: lim sin - Hint the substitution [((u-1)E)s01 u= t-n makes life 1. tm easier. Work inside the [...] first and then take the sine of your result, that is, use the rule that allows you to take the limit inside the sine function: lim sin(f(x)) n(Hm/s) sin x-a 2. Use the results we derived in class for power functions to find the derivative of g(x) (3x4 + v 4 atx Ans 3. When a function...