Recent content by scolon94

I'm still confused because of the -2xy and -2yz. Is it possible to complete the square?

x2-2xy +2y2-2yz+z2=0 hint: 2y2=y2+y2 I thought of replacing 2y^2. But I'm not sure exactly what to do. Thank you.

I get sqrt(v1^2+ v2^2+v3^2) = a^2 sqrt(V1^2+V2^2+V3^2) +b^2 sqrt(V1^2+V2^2+V3^2) + c^2 sqrt(V1^2+V2^2+V3^2)

I'm not sure if this is the correct way. va1*vb1 + va2*vb2 + va3*vb3 = av1*av1 + bv2*bv2 +cv3*cv3 Or can I put on the right side the norm of V ^2 because of one of the properties ?

Re: These two problems are based on Vectors, dot product and distance for sphere. PLEASE PLEASE HELP 1 and 2. I get it now. thank you ! how about the second problem ?

Re: These two problems are based on Vectors, dot product and distance for sphere. PLEASE PLEASE HELP This is exactly what I did, I did get sqrt(61). But my professor e-mailed me saying " This is the start of the problem. You need to find the distance between the spheres, not between the radii."

For the first problem I did distance formula. the sqrt ((x-xo) + (y-yo) + (z-zo)) as a result i got sqrt(16). I'm confused what to do after. Problem#2 I really don't understand what to do whatsoever. since abc are numbers I can't apply dot product. I thought of dividing by v on both sides but it...

Problem 1: Let S1 be a sphere centered at(0, 1, -3) with radius 1 and let S2 be a sphere centered at (3, 5, -9) with radius 2. Find the distance between the two spheres. problem 2: Given three non-zero vectors v1, v2, v3 we say that they are mutually orthogonal when v1 dot v2= 0, v1 dot v3=0 ...