Respuesta :

Answer:

[tex]comp_ab=\left(\dfrac{-5}{7}\right)[/tex]

[tex]Proj_ab=\left<\dfrac{15}{49},\dfrac{30}{49},\dfrac{-10}{49}\right>[/tex].

Step-by-step explanation:

The given vectors are

[tex]\vec{a}=<-3,-6,2>,\vec{b}=<1,1,2>[/tex]

Now,

[tex]|\vec{a}|=\sqrt{(-3)^2+(-6)^2+(2)^2}[/tex]

[tex]|\vec{a}|=\sqrt{9+36+4}[/tex]

[tex]|\vec{a}|=\sqrt{49}[/tex]

[tex]|\vec{a}|=7[/tex]

[tex]\vec{a}\cdot \vec{b}=(-3)(1)+(-6)(1)+(2)(2)[/tex]

[tex]\vec{a}\cdot \vec{b}=-3-6+4[/tex]

[tex]\vec{a}\cdot \vec{b}=-5[/tex]

The scalar projection of b onto a is

[tex]comp_ab=\left(\dfrac{\vec{a}\cdot \vec{b}}{|\vec{a}|}\right)[/tex]

[tex]comp_ab=\left(\dfrac{-5}{7}\right)[/tex]

Vector projection of b onto a is

[tex]Proj_ab=\left(\dfrac{\vec{a}\cdot \vec{b}}{|\vec{a}|}\right)\left(\dfrac{\vec{a}}{|\vec {a}|}\right)[/tex]

[tex]Proj_ab=\left(\dfrac{-5}{7}\right)\left(\dfrac{<-3,-6,2>}{7}\right)[/tex]

[tex]Proj_ab=\left<\dfrac{15}{49},\dfrac{30}{49},\dfrac{-10}{49}\right>[/tex]

Therefore, scale and vector projections of b onto a are [tex]comp_ab=\left(\dfrac{-5}{7}\right)[/tex] and  [tex]Proj_ab=\left<\dfrac{15}{49},\dfrac{30}{49},\dfrac{-10}{49}\right>[/tex] receptively.