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If a + b and a - b are perpendicular and...

If a + b and a - b are perpendicular and `b = 3hat(i) - 4hat(j) + 2hat(k)`, then |a| is equal to

A

`sqrt(41)`

B

`sqrt(39)`

C

`sqrt(19)`

D

`sqrt(29)`

Text Solution

Verified by Experts

The correct Answer is:
D
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