A sequence (xn) converges quadratically to x if there is some Q
∈ R such that |xn − x| ≤ Q/n^2
for all n ∈ N. Prove directly that if (xn) converges
quadratically, then it is also Cauchy.
What it means the degree of g(x) is 0?
(g(x) is a non zero element of N of minimal degree. Where N is an
ideal in F[x]. )
the geometrical meaning of degree of polynomial is 0?
Let {λn} be a sequence of scalars that converges to
zero, limn→∞ λn = 0. Show that the operator A
: ℓ2 → ℓ2 , A(x1, x2,
..., xn, ...) = (λ1x1,
λ2x2, ..., λnxn, ...)
is compact. What is the spectrum of this operator?
Using field axioms, prove the following theorems:
(i) If x and y are non-zero real numbers, then xy does not equal
0
(ii) Let x and y be real numbers. Prove the following
statements
1. (-1)x = -x
2. (-x)y = -(xy)=x(-y)
3. (-x)(-y) = xy
(iii) Let a and b be real numbers, and x and y be non-zero real
numbers. Then a/x + b/y = (ay +bx)/(xy)
Prove that the range of a matrix A is equal to the number of
singular non-null values of the matrix and Explain how the
condition number of a matrix A relates to its singular values.