In: Advanced Math
Prove and apply the fundamental theorem of calculus in finding the value of specific Riemann integrals of functions. This is for a class in real analysis. Right now, I just need a basic understanding. Thank you.
In: Advanced Math
Let X = R and A = {disjoint union of the intervals of the form (a, b], (−∞, b] and (a, + ∞)}. Prove that A is an algebra but not a σ-algebra.
In: Advanced Math
1. Prove``The left and right cosets partition G into equal sized chunks." (Cor 5.11 and 5.13 in your book). You have to show the ~ is an equivalence relation, you can't just cite a theorem from the book. Similarly so you have to show phi is 1-1 and onto, you can't just cite a theorem from the book.
(Corollary 5.11. If G is a group and H ≤ G, then the left (respectively, right) cosets of H form a partition of G. Next, we argue that all of the cosets have the same size)
(Corollary 5.13. Let G be a group and let H ≤ G. Then all of the left and right cosets of H are the same size as H. In other words #(aH) = |H| = #(Ha) for all a ∈ G. † The next theorem provides a useful characterization of cosets. Each part can either be proved directly or by appealing to previous results in this section.)
2. Use the above theorem to prove Lagrange's theorem. (Don't use a proof you read online or in the book, your goal is to prove it using what you know about cosets).
In: Advanced Math
(a) Find a linear transformation T : R2→R2 that (i) maps the x1-axis to itself, (ii) maps the x2-axis to itself, and (iii) maps no other line through the origin to itself.
For example, the negating function (n: R2→R2 defined by n(x) =−x) satisfies (i) and (ii), but not (iii).
(b) The function that maps (x1, x2) to the perimeter of a
rectangle with side lengths x1 and x2 is not a linear
function. Why?
For part (b) I can't come up with any counterexamples that show
T(x+y) = T(x) + T(y) or that aT(x) = T(ax) isn't true, and when I
tried to use a variables instead of numbers, I ended up showing
that it did satisfy both conditions. I'm not sure what I'm
missing.
In: Advanced Math
Determine which of the following pairs of functions y1 and y2 form a fundamental set of solutions to the differential equation: x^2*y'' - 4xy' + 6y = 0 on the interval (0, ∞). Mark all correct solutions:
a) y1 = x and y2 = x^2
b) y1 = x^2 and y2 = 4x^2
c) y1 = x^2 and y2 = x^3
d) y1 = 4x^2 and y2 = x^3
e) y1 = [(x^2)+(x^3)] and y2= x^3
In: Advanced Math
Solve Laplace's equation inside a rectangle 0 ≤ x ≤ L, 0 ≤ y ≤ H, with the following boundary conditions [Hint: Separate variables. If there are two homogeneous boundary conditions in y, let u(x,y) = h(x)∅(y), and if there are two homogeneous boundary conditions in x, let u(x,y) = ∅(x)h(y).]:
∂u/∂x(0,y) = 0
∂u/∂x(L,y) = 0
u(x,0) = 0
u(x,H) = f(x)
In: Advanced Math
Students at the Akademia Podlaka conducted an
experiment to determine whether the Belgium-minted Euro coin was
equally likely to land heads up or tails up. Coins were spun on a
smooth surface, and in 200 spins, 150 landed with the heads side
up. Should the students interpret this result as convincing
evidence that the proportion of the time the coin would land heads
up is not 0.5? Test the relevant hypotheses using α = 0.01. Would
your conclusion be different if a significance level of 0.05 had
been used? (For z give the answer to two decimal places. For
P give the answer to four decimal places.)z =
P = For α = 0.01
There is ---Select--- enough not enough evidence to
suggest that the proportion of the time that the Belgium Euro coin
would land with its head side up is not 0.5.
For α = 0.05
There is ---Select--- enough not enough evidence to
suggest that the proportion of the time that the Belgium Euro coin
would land with its head side up is not 0.5.
In: Advanced Math
study of the effect of college student employment on academic performance, the following summary statistics for GPA were reported for a sample of students who worked and for a sample of students who did not work. The samples were selected at random from working and nonworking students at a university. (Use a statistical computer package to calculate the P-value. Use μemployed − μnot employed. Round your test statistic to two decimal places, your df down to the nearest whole number, and your P-value to three decimal places.)
Sample
SizeMean
GPAStandard
DeviationStudents Who
Are Employed1723.120.475Students Who
Are Not Employed1143.230.524
t= df= P=
Does this information support the hypothesis that for students at
this university, those who are not employed have a higher mean GPA
than those who are employed? Use a significance level of 0.05.
YesNo
In: Advanced Math
Let S ⊆ R and let G be an arbitrary isometry of R . Prove that the symmetry group of G(S) is isomorphic to the symmetry group of S. Hint: If F is a symmetry of S, what is the corresponding symmetry of G(S)?
In: Advanced Math
Determine the eigenvalues and eigenfunctions of the following operator (assume σ(x) ≡ 1): L(u) = u''−2u x ∈ (−1,1) with periodic boundary conditions u(−1) = u(1), u'(−1) = u'(1). Box your final answer
In: Advanced Math
1-f(x) =1/8(7x-2), x ≤ 3
a-absolute maximum value b-absolute minimum value c-local maximum value(s) d-local minimum value(s)
2-Show that the equation x3 − 16x + c = 0 has at most one root in the interval [−2, 2].
3-If f(1) = 10 and f '(x) ≥ 3 for 1 ≤ x ≤ 4, how small can f(4) possibly be?
In: Advanced Math
Write your own R-function for the linear regression using qr() function. You must not use solve() function. The input of your function would be a design matrix X and a response vector y and the output must contain
- least sqaure estimates and the corresponding stnadard errors.
- residuals and MSE
- fitted values
- ANOVA table
In: Advanced Math
Solve IVP for y(x): dy/dx + (3/x)y = 8y^4, y(1) = 1
In: Advanced Math
Find the values of λ (eigenvalues) for which the given problem has a nontrivial solution. Also determine the corresponding nontrivial solutions (eigenfunctions).
y''+2λy=0; 0<x<π, y(0)=0, y'(π)=0
In: Advanced Math