Recent content by Pizzerer

Homework Statement Write out a tree (this will be a big tree) of dependencies and hence write down an expression for ∂z/∂rHomework Equations z=k(x, y)=xy2, x=(w1)(w2)+w3, y=w4; w1=t, w2=t2, w3=2t+1, w4=sin(t); t=r2+2s2The Attempt at a Solution This is the tree I drew and followed the...

Thanks for all the help, guys. I appreciate it.

Ah! Sweet, that makes complete sense. Thanks a million!

I just went over my notes. It seems I can only use the 'cutting out of corners' method when I have an actual value associated with the width, breath and height. I have no numerical values other the fact that the surface area = 12m2

I'm pretty sure. I even looked over some tutorial notes online and the V=xy(12-xy)/(2x+2y) formula was mentioned. I know of the method with cutting out the corners. I'll try that now instead, but my lecturer has, annoyingly, failed to provide the final answer to the problem, so I can't even...

Homework Statement I have 12m2 of cardboard. I must make a rectangular box with no lid, but I must maximize the potential volume of the box. The length, width and height of the box are x,y,z.Homework Equations I know that xyz = V (volume). I know the surface area is 12m2 ∴ 2xz+2yz+xy=12...

How do I find the potential y values for 32y^3-168y+100=0 It's a multi-variable calc problem. I have to find the critical points of the surface f(x,y) = 10yx^2 - 5x^2 - 4y^2-x^4-2y^4 ∂f/∂x = 20xy-10x-4x^3 = 0 x=0 or x^2 = (20y-10)/4 ∂f/∂y = 8y^3+8y-10x^2=0 I subbed x^2 in and got...

Could you explain to me how you got those figures?

I'm not very good at probability and I'm just having trouble interpreting and calculating what the questions actually want me to do. Could someone please help to explain this simply? 1.Five cards are dealt at random from a standard pack. Ignoring suit, what is the probability that at least...