# Math Help - Converting Cones in Spherical Polar Coor to Cartesean.

1. ## Converting Cones in Spherical Polar Coor to Cartesean.

Find an equation in rectangular coordinates of the quadric surface consisting of the following two cones.

I havent a CLUE how to start this

i was thinking of converting the cones via the normal conversion methods, but then i lost myself

ive never dealt with conical surfaces in any spaces...

2. z= pcos(phi)

z= sqrt(x^2+y^2+z^2)cos(phi)

z^2 = (x^2 +y^2 +z^2)cos^2(pi/6)

z^2 = 3/4(x^2 +y^2 +z^2)

z^2/4 = 3/4(x^2 +y^2)

z^2 = 3(x^2 +y^2)

z = sqrt(3)sqrt(x^2 + y^2)

thanks dude

4. Note fro phi = 5pi/6 the cone is in the bottom four octants

The calculation is the same but take the negative sqrt of z

z = - sqrt(3)sqrt(x^2 + y^2)

5. that worked well enough
i should of seen that but oh well

thanks again