Find [tex]\| v \|-\| w \|[/tex], if [tex]v =-6 i +4 j[/tex] and [tex]w =-3 i +2 j[/tex].

[tex]\| v \|-\| w \|=[/tex]

[tex]\square[/tex]

(Type an exact answer, using radicals as needed. Simplify your answer.)



Answer :

To find [tex]\(\| v \| - \| w \|\)[/tex] for the vectors [tex]\(v = -6\mathbf{i} + 4\mathbf{j}\)[/tex] and [tex]\(w = -3\mathbf{i} + 2\mathbf{j}\)[/tex], we need to follow these steps:

1. Find the magnitude (norm) of [tex]\(v\)[/tex]:

The norm of a vector [tex]\(v = a\mathbf{i} + b\mathbf{j}\)[/tex] is given by:
[tex]\[ \| v \| = \sqrt{a^2 + b^2} \][/tex]

For [tex]\(v = -6\mathbf{i} + 4\mathbf{j}\)[/tex]:
[tex]\[ \| v \| = \sqrt{(-6)^2 + 4^2} \][/tex]
[tex]\[ \| v \| = \sqrt{36 + 16} \][/tex]
[tex]\[ \| v \| = \sqrt{52} \][/tex]
[tex]\[ \| v \| = \sqrt{4 \cdot 13} \][/tex]
[tex]\[ \| v \| = 2\sqrt{13} \][/tex]

2. Find the magnitude (norm) of [tex]\(w\)[/tex]:

Again, using the formula for the norm of a vector for [tex]\(w = -3\mathbf{i} + 2\mathbf{j}\)[/tex]:
[tex]\[ \| w \| = \sqrt{(-3)^2 + 2^2} \][/tex]
[tex]\[ \| w \| = \sqrt{9 + 4} \][/tex]
[tex]\[ \| w \| = \sqrt{13} \][/tex]

3. Calculate the difference between the magnitudes:

[tex]\[ \| v \| - \| w \| = 2\sqrt{13} - \sqrt{13} \][/tex]

Factor out [tex]\(\sqrt{13}\)[/tex]:
[tex]\[ \| v \| - \| w \| = \sqrt{13}(2 - 1) \][/tex]

Simplify:
[tex]\[ \| v \| - \| w \| = \sqrt{13} \][/tex]

Putting it all together:
[tex]\[ \| v \| - \| w \| = \sqrt{13} \][/tex]

Thus, the exact answer is:
[tex]\[ \sqrt{13} \][/tex]