MathsJEE Main 21 Jan 2026, Shift 1·Q5·MCQ·Moderate

Vectors · Vector cross product equations

Let

\vec a = -\hat i + 2\hat j + 2\hat k

,

\vec b = 8\hat i + 7\hat j - 3\hat k

and

\vec c

be a vector such that

\vec a\times\vec c = \vec b

. If

\vec c\cdot(\hat i + \hat j + \hat k) = 4

, then

\lvert\vec a + \vec c\rvert^2

is equal to:

(1)33
(2)30
(3)35
(4)27

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