If the vectors $$\left( {\hat i + \hat j + \hat k} \right)$$ and $$3\hat i$$ form two sides of a triangle, the area of the triangle is :
A.
$$\sqrt 3 $$
B.
$$2\sqrt 3 $$
C.
$$\frac{3}{{\sqrt 2 }}$$
D.
$$3\sqrt 2 $$
Answer :
$$\frac{3}{{\sqrt 2 }}$$
Solution :
The area of the triangle
$$A = \frac{1}{2}\left| {\left( {\hat i + \hat j + \hat k} \right) \times \left( {3\hat i} \right)} \right| = \frac{3}{{\sqrt 2 }}.$$
Releted MCQ Question on Basic Physics >> Kinematics
Releted Question 1
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