If the side AB of an equilateral triangle ABC lying in the xy plane is denoted by the vector 3i,then side CB is denoted by the vector, is

Question

If the side AB of an equilateral triangle ABC lying in the xy plane is denoted by the vector 3i,then side CB is denoted by the vector, is (A) (-3/2)( hat i -√3 hat j ) (B) (-3/2)( hat i +√3 hat j ) (C) (3/2)( hat i -√3 hat j ) (D)  (3/2)( hat i +√3 hat j )

Tardigrade Admin · Accepted Answer

MC =3 sin 60°=(3 √3/2) MC =(3 √3/2) hat j text Now MC + CB = MB (3 √3/2) hat j + CB =(3/2) hat i CB =(3/2)( hat i -√3 hat j )

Q. If the side $A B$ of an equilateral triangle $A BC$ lying in the xy plane is denoted by the vector $3 i$ ,then side $CB$ is denoted by the vector, is

$\frac{- 3}{2} (\hat{i} - 3 \hat{j})$

$\frac{- 3}{2} (\hat{i} + 3 \hat{j})$

$\frac{3}{2} (\hat{i} - 3 \hat{j})$

$\frac{3}{2} (\hat{i} + 3 \hat{j})$

$MC = 3 sin 6 0^{\circ} = \frac{3 3}{2}$
$MC = \frac{3 3}{2} \hat{j}$
$Now MC + CB = MB$
$\frac{3 3}{2} \hat{j} + CB = \frac{3}{2} \hat{i}$
$CB = \frac{3}{2} (\hat{i} - 3 \hat{j})$

Q. If the side AB of an equilateral triangle ABC lying in the xy plane is denoted by the vector 3i,then side CB is denoted by the vector, is

2−3​(i^−3​j^​)

2−3​(i^+3​j^​)

23​(i^−3​j^​)

23​(i^+3​j^​)