Homework Statement
Show that if (x_{n}) is a sequence in a metric space (E,d) which converges to some x\inE, then (f(x_{n})) is a convergent sequence in the reals (for its usual metric).
Homework Equations
Since (x_{n}) converges to x, for all ε>0, there exists N such that for all...
Homework Statement
If a, b, and c are any three vector fields in locally Minkowskain 4-manifold, show that the field ε_{ijkl}a^{i}b^{k}c^{l} is orthogonal to \vec{a}, \vec{b}, and \vec{c}.
Homework Equations
The Attempt at a Solution
I know I have to show that multiplying the...
Homework Statement
Consider the ellipsoid L \subsetE3 specified by
(x/a)^2 + (y/b)^2 + (z/c)^2=1
(a, b, c \neq 0). Define f: L-S^{2} by f(x, y, z) = (x/a, y/b. z/c).
(a) Verify that f is invertible (by finding its inverse).
(b) Use the map f, together with a smooth atlas of S^{2}, to...
Homework Statement
One of the quantum mechanics wave functions of a particle of unit mass trapped in an infinite potential square well of width 1 unit is given by
Ψ(x,t)= sin(\pix)e^{-i(\pi^2\overline{h}/2)t} + sin(2\pix)e^{-i(4\pi^2\overline{h}/2)t}\
where \overline{h} is a certain...
Homework Statement
Define f as: f(x)= 2 if 0\leqx<1
f(1)=0
f(x)= -1 if 1<x<2
f(2)= 3
f(x)=0 if 2<x<3
f(3)=1
Prove f is integrable using six subintervals and find the value of \intf(x) dx
The Attempt at...
Homework Statement
Prove Q[sqrt 2, sqrt 3] is a field.
Homework Equations
Q[sqrt 2, sqrt 3]= {r + s\sqrt{2} + t\sqrt{3} + u\sqrt{6}| r,s,t,u\in Q}
The Attempt at a Solution
I know I have to show each element has an inverse, but I don't know how on these elements.
Smallest subfields containing Z[i] and Z[sqrt2]
Homework Statement
What are the smallest subfields of R containing Z[i] and Z[\sqrt{2}]?
Homework Equations
Z[i]= {a+ib|a,b\in Z}
Z[\sqrt{2}]={a+b\sqrt{2}|a,b\in Z}
The Attempt at a Solution
Z[i]\subsetQ[i] and...
Homework Statement
Give an example of a ring monomorphism f:M(2;R)-M(3;R)
Homework Equations
The Attempt at a Solution
I can't think of anything that would be a monomorphism.
Homework Statement
Prove that if f:R-R' is a ring homomorphism, then
a) f(R) is a subring of R'
b) ker f= f^{-1}(0) is a subring of R
c) if R has 1 and f:R-R is a ring epimorphism, then f(1_{R})=1_{R'}
Homework Equations
For a ring homomorphism,
f(a+b)= f(a) + f(b)
f(ab)= f(a)f(b)...
Homework Statement
Write the multiplication table of C_{6}/C_{3}
and identify it as a familiar group.
Homework Equations
The Attempt at a Solution
C_{6}={1,\omega,\omega^2,\omega^3,\omega^4,\omega^5}
C3={1,\omega,\omega^2}
The cosets are C3 and \omega^3C3
I just need help...