Recent content by sschmiggles

I'm getting ready to register for classes for the fall. To make a long story short, I might have to take another math class to satisfy a degree requirement, rather than a computer science class. I'm taking Linear Algebra right now. I enjoy it, and it seems to have a lot of practical...

Yeah, I understand it now. This is the first class I've had to write my own proofs in, so I'm still getting used to it. Thanks again for the help.

But how do I know that there isn't a scalar that would change X in such a way that (cX)A ≠ A(cX)? Edit: I guess I get what you're saying now, but it still confuses me how I can just say that they're equal with no real evidence.

Homework Statement A is a 2 x 2 matrix. Prove that the set W = {X: XA = AX} is a subspace of M2,2Homework Equations The Attempt at a Solution I have already proven non-emptiness and vector addition. Non-emptiness: W must be non-empty because the identity matrix I is an element of W. IA = AI A...

Thanks a lot. I was making this a lot harder for myself than I needed to.

Thanks, I've got it now too, but how am I supposed to know when to subtract the width/height from x without looking at a graph? I just did a very similar problem (y = 8 - x^3), subtracted from x for the height, and got the wrong answer. I got the right answer when I didn't subtract h from x...

Homework Statement y = x^(1/3) - 2 Find volume across the x-axis on 8 <= x <= 27 using the Method of Shells Homework Equations V = 2pi * Integral(r * h) from a -> b The Attempt at a Solution Let x = (y + 2)^3 Let h = (y +2)^3 // Set height Let r = y // Set...