I know, this is only one case of three other cases. I'm trying to prove, exhaustively, that for the union of three subspaces to be a subspace one of them must contain both of them.
The first case I consider is if this condition (x ∈ Ua and y ∈ Ub then x+y belongs to either one of them, as...
Yeah, I apologize for the mess. I found it very difficult to organize my thoughts regarding this question and I ended up writing it in an unclear way.
What I'm trying to prove is this:
(Union of three subspaces of V is a subspace of V) ##\Rightarrow## (One of the subspaces contains the other...
Homework Statement
This is the exact phrasing form Linear Algebra Done Right by Axler:
Prove that the union of three subspaces of V is a subspace of V if and only if one of the subspaces contains the other two. [This exercise is surprisingly harder than the previous exercise, possibly because...
I'm taking a course in chemistry and I need some help, I have some questions :
1.Why do ions, strong acids,bases etc. conduct electricity well ?
2.In the periodic table, are the masses of atoms in amu or grams? what's the difference? and why is Carbon 14 the standard ? why do we need a...
Ok here is the original equation :
Cu+HNO3 = Cu(NO3)2+NO2+H2O
Now according to "The Oxidation Number Method", I must balance the charges first
and if you look at the equation you will find that :
Cu -> lost 2electrons
N -> gained 1electron
Then balance the charges by multiplying N by 2, so I...
Help in "The Oxidation Number Method"?
Homework Statement
I just learned how to balance the redox reactions with this method, but there is something I don't understand ...
Look at this example :
Cu+HNO3 = Cu(NO3)2+NO2+H2O
after making the number of electrons gained and lost equal we get...
Hey guys
I was in a discussion with my friend and I couldn't answers some questions about evolution .. and since I'm not that good in biology, I hope that I get some explained answers.
Q1 : How can mutations produce organs ?
Q2 : Do genetic mutations produce positive and negative changes ...
It's just an example for me to understand something, but I didn't know that it missed some additional info sorry, lol.
Let's suppose that the angle is 45 degree.
Both arrows have the same angles
http://imageshack.us/photo/my-images/337/drawingz.png/
How can I find the net force of this and the direction ?
Thanks.
Hey guys
I'm a new member and I will be mostly asking questions :P
Anyways ...
Physics subjects in my school are about electricity now and my teachers aren't very good, so I can't clearly understand what they're saying.
To get to the bottom line, our lesson was about electrons and...