Recent content by Superdemongob

This is not a homework problem but in fact a solved example question. The full question text is below with answers and my reasoning for them. Could someone please explain the reasoning behind part (c). A coffee shop sells 5 types of coffee (latte, mocha, espresso, cappuccino and iced...

thank you so so much. i'm studying for a test and this helps a LOT. thanks again.

I think I finally get it. You take the inverse of the coefficients and that is your directional vector?

I get what you mean but how do you know that that is the directional vector? Like what is the method for finding out? If the question had the line 2(x−1) = y − 1 = -3(z−2) then how would the directional vector be different? Sorry but I'm really trying to understand this.

1. Question: Find the directional derivatives of f(x, y, z) = x2+2xyz−yz2 at (1, 1, 2) in the directions parallel to the line (x−1)/2 = y − 1 = (z−2)/-3. 2. Solution: We have ∇f = (2x + 2yz)i + (2xz - z2)j + (2xy - 2yz)k. Therefore, ∇f(1, 1, 2) = 6i - 2k. The given line is...

EDIT: I totally just got it. Thank you so much for your prompt response. Sorry, i know that I'm being really thick on this and once i see it i'll kick myself but 1 follow up question if you don't mind. is the reason you know that -101\equiv -10 ~\mbox{mod} ~13 because you know that the...

This is a very basic question that I am having some difficulty grasping. When I do the long division for -101 / 13, my first step is -7 which comes out to -91 and so I have left -10. Shouldn't this be where the calculation stops? One of the thoughts I had was that as -13 is smaller...

So, I've browsed PF and found it to be awesome in terms of advice. I've already read some of the threads that about the IB Physics extended essay. Some basic information: Education level is Grade 11/12 I can handle quite advanced physics. The actual Extended Essay is a 4000 word in depth...