00:01
Hi, for the position vectors p and q, we need to find the vector pq and the termini's direction cosine.
00:09
So let's say the origin is o.
00:12
Then the vector opi is shown here, and the vector oq is shown here according to the coefficients.
00:21
Then from this triangle, we can see that vector opi plus pq is equal to oq.
00:28
From there, pq is equal to oq minus op.
00:32
And having the oq and op coefficients here, we can determine.
00:37
They would have pq is equal to 5i minus 2j plus 4k minus i plus 3j minus 7k.
00:57
This gives us 4i minus 5j plus 11k.
01:09
This is the vector pq.
01:12
Now for the direction cosines, first of all let's calculate the magnitude of pq, which is under the square root, the first coefficient square, 4 square, plus the second coefficient square, which is minus 5 square, plus the third coefficient square...