Wat is the equation of a sphere?
Does it indicate that a point is on the surface of the sphere, or that a point is in the sphere itself?

Question

jim_thompson5910 · Answer

Point that is on the surface of the sphere.

anonymous · Answer

Depends whether u are a physicist or a math person..:-)

anonymous · Answer

I am talkimg about math

anonymous · Answer

i dont get this

anonymous · Answer

Says the champion :)

anonymous · Answer

its on the surface, if it were inside the sphere the equation would be like$$(x-a)^2+(y-b)^2+(z-c)^2<r^2$$

anonymous · Answer

That is not an equation.

jim_thompson5910 · Answer

but that's not an equation anymore dodomaroc, it's an inequality.

anonymous · Answer

But otherwise you are correct

anonymous · Answer

Do you mean a formula for its volume or its surface area?

anonymous · Answer

Neither.

jim_thompson5910 · Answer

neither volume nor surface area, this equation simply shows you which points lie on the surface of the sphere and when graphed, the visual is a sphere.

myininaya · Answer

do you how we say (x-h)^2+(y-k)^2=r^2
is the equation of a circle right?

anonymous · Answer

Ya

anonymous · Answer

n-sphere..

anonymous · Answer

wats an n-sphere?

myininaya · Answer

i bet we could use the distance formula to show the equation of a sphere like we can use the distance formula to show the equation of a circle

myininaya · Answer

but we have 3 dimensions and instead of 2

anonymous · Answer

http://www.youstupidrelativist.com/01Math/08Solid/02Dim.html

myininaya · Answer

so
distance
$$d=\sqrt{(x-x_1)^2+(y-y_1)^2+(z-z1)^2}$$

anonymous · Answer

hmmm. interesting

myininaya · Answer

dang it stupid subscripts

anonymous · Answer

So does this shows the distance between what???

myininaya · Answer

$$d=\sqrt{(x-x_1)^2+(y-y_1)^2+(z-z_1)^2}$$

myininaya · Answer

$$d^2=(x-x_1)^2+(y-y1)^2+(z-z1)^2$$
center is $$(x_1,y_1,z_1)$$
its the distance from a point on the sphere to the center of the sphere

anonymous · Answer

r^2 = sum i=1 to n+1 (x_i-c_i)^2