A) a vector from C(3,2,-7) to D(-1,-4,2)
B) a unit vector at D directed toward C
C) a unit vector at D directed toward the origin.
The answers are
a) -6.66 -2.77+9 b)-0.59+0.21-0.78 c)-0.90 -0.44
But i don't know how they get them.
Can anyone please show me?
2007-09-08 07:21:12 · 2 answers · asked by su 2 in Science & Mathematics ➔ Engineering
In the same way that a point can be described in a plane by either 2 linear dimensions (x, y) or by a length and an angle (r, Φ), there are basically 3 ways to describe a point in 3-space:
3 linear dimensions (x, y, z)
2 angles and a length (Φ,Θ,r)
or an angle and 2 lengths (Φ, r, z)
A really detailed discussion of how to transform between the 3 would take -way- too much space here, but you should find it in pretty much any 2'nd year Calculus book or anything on solid geometry.
HTH
Doug
2007-09-08 07:40:02 · answer #1 · answered by doug_donaghue 7 · 0⤊ 0⤋
get
Schaum's Outline of Electromagnetics
amazon.com
2007-09-08 07:43:25 · answer #2 · answered by mike 5 · 0⤊ 0⤋