Let OABC be a parallelogram, O be the origin, A (2, 4, −5) and C (b, 2, 3). If P (a, a, a) and Q (9 − a, 3, a − 1), a ∈ ℕ, are two points such that the projection of on is 2 and makes acute angles with all three co-ordinate axes, then is equal to _______.
← JEE Main 2022 · 30 Jul · Shift 2
MathematicsInteger+4 / -1Question 88 of 90
JEE Main 2022 · 30 Jul · Shift 2, Mathematics question 88
Answer and worked solution
Official answer: 118
Find a. Acute angles with all axes need and : , so P = (2, 2, 2).
Find b. . Projection gives .
Sum .
Answer: 118
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