If a⃗ = 5i − j − 3k and b⃗ = i + 3j − 5k, then a⃗ + b⃗ and a⃗ − b⃗ areयदि a⃗ = 5i − j − 3k तथा b⃗ = i + 3j − 5k, तब a⃗ + b⃗ और a⃗ − b⃗ होंगे
यदि a⃗ = 5i − j − 3k तथा b⃗ = i + 3j − 5k, तब a⃗ + b⃗ और a⃗ − b⃗ होंगे
Show answerHide answer
Correct answer: (B) Perpendicularलम्बवत्
Explanation
(a⃗ + b⃗)·(a⃗ − b⃗) = |a⃗|² − |b⃗|² = (25 + 1 + 9) − (1 + 9 + 25) = 35 − 35 = 0, so the two vectors are perpendicular.(a⃗ + b⃗)·(a⃗ − b⃗) = |a⃗|² − |b⃗|² = (25 + 1 + 9) − (1 + 9 + 25) = 35 − 35 = 0, इसलिए दोनों सदिश लम्बवत् हैं।