JEE Main 2026 · 6 Apr · Shift 2 · Mathematics Q15

← JEE Main 2026 · 6 Apr · Shift 2

MathematicsSingle correct+4 / -1Question 15 of 75

Let $\vec a=2\hat i+3\hat j+3\hat k$ and $\vec b=6\hat i+3\hat j+3\hat k$ . Then the square of the area of the triangle with adjacent sides determined by the vectors $\left(2\vec a+3\vec b\right)$ and $\left(\vec a-\vec b\right)$ is :

450

900

1800

2400

Answer and worked solution

Official answer: C

Sides. $2\vec a+3\vec b=(22,15,15)$ and $\vec a-\vec b=(-4,0,0)$ .

Cross product. $(0,-60,60)$ , of length $60\sqrt2$ .

Area. $30\sqrt2$ ; its square is 1800.

(C)

Topics:Cross product

← Previous question Next question →

JEE Main 2026 · 6 Apr · Shift 2, Mathematics question 15