spherical coordinates example

[npa50051]

exam coming up on this stuff... this stuff sucks

[fahdiqbal11]

z=sqrt x^2 + y^2

z=r

rhocosphi=rhosinphi divide both sides by rho

cosphi=sinphi divide both sides by cosphi

1 = tanphi

phi = arctan 1

phi= pi/4

NOT 3pi/4

[wolterh6]

@fahdiqbal11 You missed a spot there, ranger, don't be so sure about your claim. Notice that z = -r != r => (...) => tan(phi)=-1 => phi = -pi/4 = 3pi/4

[12388696]

Perfect!

[erica4123]

THANK YOUUUUUUUU!!!!!!

[DeluxeWarPlaya]

@parpsy because you measure it from the positive z axis.

[parpsy]

why three pie over four explain phi more

[TomRiverstone]

another question, sorry

how would you find the angle phi if the cone is given by z = 7sqrt(x^2+y^2)? and you're looking for the area inside a sphere of radius 6 inside that cone?

[albi7]

@TomRiverstone When you have z = a*sqrt(x^2 + y^2) it is tan(phi) = 1/a

[TomRiverstone]

I have a request, if possible, can you do a series on real analysis???

[TomRiverstone]

man I wish this stuff was around when I took the class... makes me wanna cry lol, I took Calc III with many, many hard classes and just couldn't find time

[tomhuu2]

not rly understaindg the 3pi/4 to pi part, but i suck at math lol

[icevermin]

It's a John Coltrane song. I forget which. How do you find the centroid of a region? I'm so confused by spherical coordinates

[YellowYackets]

hey! love the intro jazz song.. whats the name?

[felenoral]

giant steps by john coltrane

[sunrise3500]

don't understand, if: (x^2 + y^2 + z^2)==>p^2 how does (p^2) ^(3/2) ===> p^5? Another thing I find hard to grasp is the bounds of phi, can you do more example on that?

Thanks

[feard0m]

@sunrise3500 it equals p^3, but when you multiply by the volume element you get p^5... (comes from p^2 sin )

[fushinotori1]

u might have saved me on my final

[dulerong5]

Thanks a lot, this is a helpful video

[seriallk]

Shouldnt that cone be the other way around?

[elirezz]

The region is described by z = NEGATIVE root x^2+y^2, so you will take the negative z-axis.

Gr8 Video.

[rahimoonsaga]

Excellent thanks for uploading