24 reputation
113
bio website
location
age
visits member for 2 years, 1 month
seen Sep 2 '13 at 21:17

Sep
2
awarded  Altruist
Sep
1
awarded  Investor
Jul
23
comment Prove $\sqrt{k}$ is not a rational number.
math.stackexchange.com/questions/4467/…
Jul
18
awarded  Citizen Patrol
Jul
18
comment Showing something is Riemann Integrable
What have you tried?
Jul
17
answered Find the limit if it exists. Multivariable calculus
Jul
16
comment How to solve this simple integral with substitution and partial fraction decomposition
No problem.${}$
Jul
16
comment How to solve this simple integral with substitution and partial fraction decomposition
After the substitution you should get $\displaystyle\int\frac{u^2}{(u-1)^3}\dfrac{du}{2u}=\frac12 \int\frac{u}{(u-1)^3}du$.
Jul
16
answered How to solve this simple integral with substitution and partial fraction decomposition
Jul
16
comment Proving there exist an infinite number of real numbers satisfying an equality
Are you sure that is the correct stactement?
Jul
16
comment Find equation of the plane through the origin with basis <1,2,-1> and <2,3,4>.
Yes, the vector you get when you compute the cross product is a normal vector to the plane. Since you got $11i-6j-k$ as normal vector, an equation for the plane is $11x-6y-z=0$. And don't worry, we are all learning. :)
Jul
16
comment Find equation of the plane through the origin with basis <1,2,-1> and <2,3,4>.
Yes, that's the cross product. No, that's not an equation. Given a normal vector $ai+bj+ck$ to a plane $P$ through the origin, an equation for $P$ is given by $ax+by+cz=0$.
Jul
16
answered Find equation of the plane through the origin with basis <1,2,-1> and <2,3,4>.
Jul
15
comment Find the characteristic polynomial of a matrix
You're welcome. :)
Jul
15
answered Find the characteristic polynomial of a matrix
May
28
comment finite additivity condition
I'm afraid I don't get what you mean. You're given a finite number of disjoint sets, say, $A_1,\cdots ,A_N$, and you want to prove $P(\bigcup_{n=1}^NA_n)=\sum_{n=1}^N P(A_n)$. So you construct a sequence $(B_n)_{n\in\Bbb N}$ setting $B_k=A_k$ for $1\le k\le N$ and $B_k=\emptyset$ for $k>N$. Then you apply the countable aditivity property to $B_1,B_2,\cdots$. What do you get?
May
28
comment finite additivity condition
Just set $A_n=\emptyset$ for $n>N$.
May
26
comment Proving that either $2^n-1 $ or $ 2^n+1$ is not prime
One of them must be divisible by 3.
May
25
comment Is $1847^{2013}+2$ really a prime?
Mathematica says it is prime... it took less than a minute.
May
25
comment Sequences with the following properties…
What if $b_n$ is not positive?