Given vectors A (2,-1,5), B (4,3,-2) & C (5,4,0), find:?
1 answer:
A) 4a - 3b + 2c
4(2, -1, 5) - 3(4, 3 , -2) + 2(5, 4, 0) = (8, -4, 20) - (12, 9, - 6) + (10, 8, 0) =
= (8 - 12 + 10 , -4 - 9 + 8 , 20 + 6 + 0) = (6, - 5, 26)
Answer: (6, - 5, 26)
b) magnitude of vector b
c) vector of length 7 parallel to vector c
=> m(5,4,0) = (5m,4m,0)
=>
=> m = 7 / √41 ≈ 1.093
=> 1.093 (5, 4, 0) = (5.465 , 4.372, 0)
Answer: (5.465 , 4.372 , 0)
4(2, -1, 5) - 3(4, 3 , -2) + 2(5, 4, 0) = (8, -4, 20) - (12, 9, - 6) + (10, 8, 0) =
= (8 - 12 + 10 , -4 - 9 + 8 , 20 + 6 + 0) = (6, - 5, 26)
Answer: (6, - 5, 26)
b) magnitude of vector b
c) vector of length 7 parallel to vector c
=> m(5,4,0) = (5m,4m,0)
=>
=> m = 7 / √41 ≈ 1.093
=> 1.093 (5, 4, 0) = (5.465 , 4.372, 0)
Answer: (5.465 , 4.372 , 0)
You might be interested in
The given expression is
We have to find the discriminant first . And for that, first we need to move whole terms of the left side to right side, that is
The formula of discriminant is
Substituting the values of a,b and c, we will get
And since the discriminant is greater than 0, or it is positive so we have two real roots.
Therefore the correct option is B .