Recent content by xvtsx

They are both singular and if you add them up the result would be a nonsingular matrix. Singular matrices don't have a inverse, so they aren't vector spaces.

Sorry, but can you explain what you meant? Thanks

Homework Statement The set of all 2x2 singular matrices is not a vector space. why? \begin{bmatrix} 1 & 0\\ 0&0 \end{bmatrix}+\begin{bmatrix} 0 & 1\\ 0& 1 \end{bmatrix}=\begin{bmatrix} 1 & 1\\ 0 & 1 \end{bmatrix} Homework Equations Is it because the determinant in both are zero, but by...

Honestly, I don't see it. what should I consider f(x) and g(x) ? because I only see n(x^n-1)(1)/n! as f(x).Sorry if I cause you trouble..

Oh sorry. The only thing I can say is this dx/dx= n(x^n-1)(1)/n!

okay. if the result its 1/n! how is that related to the power series?

Okay I just got a weird answer, which I think its wrong. \frac{\mathrm{d} }{\mathrm{d} x}=\frac{(n!)}{nx^{n-1}} could you give some steps cause for me its weird to differentiate explicitly with n and factorial.

Thanks for the quick reply, but I don't see how to take the derivative of the n factorial. could you please provide me with an example of how to do it?.Thanks

Homework Statement I need to demonstrate that \frac{\mathrm{d} }{\mathrm{d} x}\sum_{n=0}^{\infty }\frac{x^{n}}{n!}= \sum_{n=0}^{\infty }\frac{x^{n}}{n!} Homework EquationsThe Attempt at a Solution I just need a hint on how to start this problem, so how would you guys start this problem?

sorry for the pi part, but I use the latex editor and it only gaves that one xD.. thanks by the way. :)

Hmm.. do I raise to the power of i after I change the square root for \frac{1}{2} and multiple it with iπ ?

Homework Statement Okay, yesterday in class my teacher gave me this identity e^{i\pi }+1=0 and she wants me to rearrange the numbers around, so I can get this i^{i}= e^{-\frac{\pi}{2}} Homework Equations and The Attempt at a Solution I know that if Isolate the 1 to the other side and...

I would recommend you to take a look at It is really good book because it shows you how to solve problem [calculus 1-2]step by step, but I will also recommend you to take some classes at a community college because some of the stuff in those book are not really easy to comprehend.

Can you explain me in details how you combined that part of the fraction because I get lost here \frac{\sqrt {x^{2}+1}}{x^{2}+1}-\frac{x^{2}}{(x^{2}+1)\sqrt{x^{2}+1}}=\frac{1}{\sq rt{x^{2}+1}}-\frac{x^{2}}{(x^{2}+1)^{\frac{3}{2}}}.

Hi everyone, I have been trying to do this problem in both ways but I can't get the same answer the book says. This is the problem: x/ sqrt (x^2 +1) With quotient rule I got until the point I have [(x^2 +1)^1/2 - x^2/(x^2 +1)^1/2]/(x^2 +1) And with power rule I have [1/sqrt(x^2 +1)] -...