Question

Express the following vector in the form v=v1i+v2j+v3k. 3u - v if u=(4,7,-3) and v=(2,-7,5).3u - v = ____ i + ____ j + _____ k.(Simplify your answers.)

Answer 1

Answer:

5i+14j-7k

Step-by-step explanation:

Given the vectors u = (4,7,-3) and v=(2,-7,5), both vectors are 3-dimensional in nature and can also be rewritten as;

u = 4i+7j-3k and v = 2i-7j+5k

To get 3u-v, we will substitute the given vectors into the expression;

3u-v = 3(4i+7j-3k) -  (2i-7j+5k)

open the parenthesis

3u-v = 12i+21j-9k - 2i + 7j - 5k

collect like terms

3u-v = (12i - 2i) + (21j + 7j) (-9k-5k)

3u - v = 10i+28j-14k

To simplify the answer, we will divide through by 2

3u - v = 10i/2+28j/2-14k/2

3u - v = 5i+14j-7k

Hence the simplified form of the expression is 5i+14j-7k