Recent content by mcintyre_ie

Thanks for your help. I've figured out the proof, using the dimension theorem as you suggested. It's not even that difficult once I know what result I'm moving towards.

Hi, I'm having trouble with a proof regarding the rank of the transpose of a matrix. Here's the question: Let A be an m x n matrix of rank r, which is of course less than or equal to min{m,n}. Prove that (A^t)A has the same rank as A. Where A^t = the transpose of A. I can easily...

Thanks, that's really all I wanted to know.

Yes, I know how to apply the force equation (F=Ma, etc), but what I don't understand is where the (8 + x/5) part comes from - I don't know how to firgure out that. That's my original question, and I still don't know how to do it.

Ok, so now I'm just as lost. a = v(dv/dx), right? But I still don't know what I should be doing next...

I’m still not getting it out… am I supposed to be using equations of motion to get a, which is equal to v(dv/dx) and (d^2x)/(dx^2)? I’ve been trying to do it that way, but I’m still getting nowhere. I still can't figure out where the 8m/s^2 and 9m/s^2 retardations come in. I’d be grateful for a...

The way that I usually do it is to get a force equation for the question first... then work out dv/dx etc. Any help with actually getting a force equation?

I’m having some difficulty with this question: (b) A particle starts with a speed of 20 m/s and moves in a straight line. The particle is subjected to a resistance which produces a retardation which is initially 8 m/s^2 and which increases uniformly with the distance moved, having a value of...

I found it to be r^2 = 1/4 + 1/4 + 12. We don't have the innerproduct on our course, only dot product and scalar product, so it has to be solved using either or both of those (or other *basic* rules. Ok, I'll try it, but I'm not so sure about the lim part. Thanks for the help

Hey, I’d appreciate some help with these questions: (c) Find the centre and radius of the circle x^2 + y^2 – x – y – 12 = 0. Find the equations of the tangent to this circle which are parallel to the line 7x – y = 0. Ok, so I found the line has a slope of 7, and the circle has a...

Ok, so I've tried it again... getting x=9, with a complex root when I sub that into get my two y values, which can't be right.

Um, I don't think that refers to my (current) question?

I was thinking that the 6kg mass would be the only mass to move downwards, but both the other mass and the pulley would move upwards? For some reason I was thinking that the pulley would have an acceleration of half of that of each of the masses.

Ok, so do you mean to solve the two equations simultaneously then? If that's what you mean, I just get an answer of "8x = 36"... Yes, I would also assume that "sole a system of equations" would mean the same thing throughout the english speaking world, however I am not a native english speaker...

Well yeah, but when you say "use your Algebra 2 skills" I'm just curious as to what I'm actually supposed to use...