Question
Multiple choice.
How would I answer this in a short way?
what is the distance between the skew lines L1:(0,4,-3)+s(-1,1,3),seR and L2: (1,2,5)+t(-3,2,5),teR?
a) 4 root 2
b) 7/2
c) root 2
d) (7 root 2)/2
How would I answer this in a short way?
what is the distance between the skew lines L1:(0,4,-3)+s(-1,1,3),seR and L2: (1,2,5)+t(-3,2,5),teR?
a) 4 root 2
b) 7/2
c) root 2
d) (7 root 2)/2
Answers
Steve
as your text no doubt shows, given the two lines
L1 = <b>a</b>+<b>b</b>s
L2 = <b>c</b>+<b>d</b>t
the distance between the lines is given by
(<b>a</b>-<b>c</b>).(<b>b</b>x<b>d</b>)/|<b>b</b>x<b>d</b>|
In this case, that is
(-1,2,-8).(-1,1,3)x(-3,2,5)/|(-1,1,3)x(-3,2,5)| = 15/3√2 = 5/√2
Hmmm. Better check my math.
L1 = <b>a</b>+<b>b</b>s
L2 = <b>c</b>+<b>d</b>t
the distance between the lines is given by
(<b>a</b>-<b>c</b>).(<b>b</b>x<b>d</b>)/|<b>b</b>x<b>d</b>|
In this case, that is
(-1,2,-8).(-1,1,3)x(-3,2,5)/|(-1,1,3)x(-3,2,5)| = 15/3√2 = 5/√2
Hmmm. Better check my math.
MathMate
To Sara:
I got 5/√2 as well. Perhaps it is time to check if there are typos in the question or the answer.
Also, to print s∈R, you can write
s & i s i n ; R, but skip the spaces.
I got 5/√2 as well. Perhaps it is time to check if there are typos in the question or the answer.
Also, to print s∈R, you can write
s & i s i n ; R, but skip the spaces.