Recent content by theacerf1

Thats all the question says, so confused :confused:

Please HELP! Matrix! Please help me with the below question! I have no idea how to solve this, if someone could please help me with a solution and explain what they did and how they did it, it would be such a BIG help! Thanks! :) If A is an m×n matrix with (i, j)-entry aij , let A† be the...

M = [7 -3 15 -7] a 2x2 matrix

Ah cool, thanks for the help Char. Limit, understand everything now. Just the last part of the question if you got time, Explain what this means geometrically...(Your answer should refer to a triangle.) Draw a triangle with sides a, b, c?

Matrix HELP! Ok this question is in a cd quiz from a textbook, i have no idea what the question even means or how to do it. Please help! Let M =  7 −3 15 −7 . Find all 2 × 2 matrices A = [ a b b d ] such that AM = −MA. (Note that the solutions wanted should have equal...

Ahhh i get it now! cross products are anti-commutative ? wat does that mean? Is this a law: a x (-b) = - (a x b)? I think illl need to prove that before i can use it

a x (-a) = 0 a x (-b) is just left as it is...right? In my question it has c x a: c x (-c) = 0 c x (-b) <--- left as it is? after doing this for all, where do i go from there? Im just going to end up with equations like c x a = c x (-b) a x b = a x (-c) b x c = b x (-a)...

Ok so i get this: c x a = -(a+b) x -(b+c) a x b = -(b+c) x -(c+a) b x c = -(c+a) x -(a+b) im confused...how am i showing a × b = b × c = c × a? I got no idea how to solve: -(a+b) x -(b+c) = -(b+c) x -(c+a) = -(c+a) x -(a+b)

ahhh right ok so... c=-(a+b) axb = ax(a+c) <--------- how do u get that?? axb = axa + axc axb = 0 + ax-(a+b) axb = ax-a + ax-b <------- i don't feel like I am seeing/going anywhere with this, am i doing it right?

Im still really confused bout wat Rasalhague wrote, i get what you said a x -c = c x a, but don't understand c is equal to -(a+b)...

Just looking at the first part, what do u mean when u say, "You can solve 1.i algebraically, using the fact that the cross product distributes over addition, for example, a x c = a x (a + b), and the fact that the cross product of a vector with itself is the zero vector." Like this is what...

Hey spamiam, no its not a homework question, iv got my exam nxt week for math and just working through different textbooks solving different problems. The textbook only gives the answer but what I want to know is how they got the answer, basically the working out as i have no idea how to solve...

HELP! Vectors... Been stuck on these 2 questions for ages, PLEASE HELP! :( (1) Let a, b and c be three vectors such that a + b + c = 0. (i) Show that a × b = b × c = c × a. (ii) Explain what this means geometrically. (Your answer should refer to a triangle.) (2) (i) Find the normal vector...

Iv been stuck on this question for hrs now, no idea how to solve it. Can someone please explain, thanks! :) Let p(x) be a cubic polynomial and p′(x) be its derivative, and suppose that p(1) = 8, p(−1) = −3, p′(2) = 0 and p′(−2) = 0. Find p(x).