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Vector Algebra question

2024 · 9 Apr · Shift 2 · Q42

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JEE Main
Mathematics
Vector Algebra
2024 · 9 Apr · Shift 2 · Q42

Vector Algebra question

2024 · 9 Apr · Shift 2 · Q42

JEE MainMathematicsVector AlgebraMCQ+4 / −1

Between the following two statements: Statement I : Let

\vec{a}=\hat{i}+2 \hat{j}-3 \hat{k}

and

\vec{b}=2 \hat{i}+\hat{j}-\hat{k}

. Then the vector

\vec{r}

satisfying

\vec{a} \times \vec{r}=\vec{a} \times \vec{b}

and

\vec{a} \cdot \vec{r}=0

is of magnitude

\sqrt{10}

. Statement II : In a triangle

A B C, \cos 2 A+\cos 2 B+\cos 2 C \geq-\frac{3}{2}

.

A
Both Statement I and Statement II are correct.
B
Both Statement I and Statement II are incorrect.
C
Statement I is correct but Statement II is incorrect.
D
Statement I is incorrect but Statement II is correct.

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