0:00
Hello guys.
00:01
So for this exercise we got these three vectors here.
00:07
So for the part a we need to compute the norm of three times the vector u minus five times the vector v and plus the vector w.
00:23
Okay, so we need to compute this norm.
00:26
So let's first compute the summation inside of the norm.
00:31
So three u is just minus 6, minus 3, and 12, 15.
00:42
Okay.
00:44
Then minus 5 times the vector v is minus 15, minus 5, 25, and minus 35.
01:04
Okay.
01:05
And w, well, w is just the same vector, is minus 6, 2, 2.
01:11
Two, one, one.
01:13
So let's sum all these three vectors together and we obtain that, so 3u minus 5b plus w is 27 minus 6, minus 6, 38 and minus 19.
01:50
Okay, and now let's compute the norm.
01:53
So the norm of 3u minus 5b plus w is, well the square root of 27 square plus 6 square plus 38 square plus 19 square.
02:13
And this is the square root of 200, of 200, 250, 2 ,000, 5 ,000, 570.
02:30
6 -70 that's the solution now let's see what happened with the part b which is the norm of 3 times the vector u minus 5 times the norm of the vector v and plus the norm of w so we know that we can take this out and we just have 3 the norm of u and this is just 3 times the square root of 2 square plus 1 plus 4 square plus 5 square and this is just 3 times the square root of 46 then we got minus 5 the vector v the normal the vector b so this is minus 5 the square root here of of 3 squared plus 1 plus 5 squared plus 7 squared...