Maths-
General
Easy
Question
The position vectors of P and Q are 
and
respectively. If the distance between them is 7, then the value of a will be
- –5, 1
- 5, 1
- 0, 5
- 1, 0
The correct answer is: –5, 1
Given 
= 7
40 + (2 + a)2 = 49
(2 + a)2 = 9
2 + a = ± 3
a = 1, – 5
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