Recent content by violette

hi thanks! means I can try any ways in hope that one way will prove that limit does not exist? how can i prove that limit exist then? thanks =)

Homework Statement lim(x,y)->(0,0) x2y / 2x3-y3 Homework Equations The Attempt at a Solution I found lim f(x,0)=0 and lim f(0,y)=0.So i assume limit exists and equals 0? I would like to get some tips on how to solve this type of problems?Do I always find f(x,0) and f(0,y)?Because I...

Ah yes I manage to get! THANKS! =D

hi thanks for the reply =) but what about yz plane?

Hi!Can anyone please help me out with this question? Appreciate any help,thanks! Rewrite the integral: ∫0<x<1 ∫0<z<1-x2 ∫0<y<1-x dxdzdy into this form: \int\int\int dxdydz How do I change the integrals?Can any kind souls teach me how to sketch the diagram?I can't visualise it >.<...

omg thanks so much!The diagram made it easier for me to try on my own =) Ah oopx,it should be this: ∫(0 ≤ x ≤ 1)∫(√(1-x2) ≤ y ≤ √(3-x2)∫(1 ≤ z ≤ √(4-x2-y2) z2xy dzdydx Hmm,actually I got 3 values for x after all the conversion: 0,1 and \sqrt{3}. But I used 0 and 1 because they are the...

Hi I like Serena,really thanks so much for being so helpful =D hmm...how do I draw with cylindrical coordinates?I only know how to make a drawing given rectangular coords >.< this was what I got: ∫(0 ≤ z ≤ 1)∫(√(1-x2) ≤ y ≤ √(3-x2)∫(1 ≤ x ≤ √(4-x2-y2) z2xy dzdydx

Ah I see..thanks so much =D

oh man!u mean to use spherical coordinates,the surface has to be round?! i never knew that =S

oh no,sorry i think i did it wrongly. Im trying to convert to spherical coordinates. 0 ≤ θ ≤ 2\pi 0 ≤ ρ ≤ \frac{2a}{\sqrt{3}} 0 ≤ \phi ≤ \frac{\pi}{6} Does it look right now?

Hi sorry,I still need some help on converting coordinates >.< Set up an integral in rectangular coordinates equivalent to the integral ∫(0 ≤ θ ≤ \frac{∏}{2})∫(1 ≤ r ≤ \sqrt{3})∫(1 ≤ z ≤ √(4-r2)) r3(sinθcosθ)z2 dz dr dθ Arrange the order of integration to be z first,then y,then x. I...

Why is that so? cosine \frac{\pi}{6}=\frac{\sqrt{3}}{2},hence my \rho is 2/\sqrt{3}z?

Ah I see,so for cone, ρ will be in terms of z all the time?

Hi thanks for the replies =) but may I know why do we need to change it to cylindrical coords?I thought spherical would be better? for my spherical coords, i got: 0 ≤ z ≤ a 0 ≤ θ ≤ 2∏ 0 ≤ ρ ≤ (2a)/√3 can i also ask,is θ always between 0 and 2∏?How do we determine whether it is or...

Hi everyone, I have problems solving triple integral question like this: Find the volume of the solid bounded below by the cone \varphi=\frac{\pi}{6} and above by the plane z=a. I can do simple triple integration questions,but can some please give me some guidance on how to solve triple...