Answer:
a+b = [2, -2, 2]
a+3b = [2,2,1]
|a| = 6
[tex]|a-b|=\sqrt{65}[/tex]
Step-by-step explanation:
[tex]a+b = [2+0,-4+2,4-1]=[2,-2,2][/tex]
[tex]a+3b = [2+0,-4+6,4-3]=[2,2,1][/tex]
[tex]|a|=]sqrt{4+16+16}=\sqrt{36}=6[/tex]
[tex]|a-b|=|\sqrt{(2-0)^2+(-4-2)^2+(4+1)^2}|=\sqrt{4+36+25}=\sqrt{65}[/tex]
