Question

Let $bold a bold space bold equals bold j with bold hat on top bold minus bold k with bold hat on top bold space$ and $bold c bold space bold equals bold space bold i with bold hat on top bold minus bold j with bold hat on top bold minus bold k with bold hat on top$ . Then, the vector b satisfying a x b + c = 0 and a.b = 3

$negative straight i with hat on top plus straight j with hat on top space minus 2 straight k with hat on top$
$2 straight i with hat on top minus straight j with hat on top space plus 2 straight k with hat on top$
$negative straight i with hat on top minus straight j with hat on top space minus 2 straight k with hat on top$
$straight i with hat on top plus straight j with hat on top space minus 2 straight k with hat on top$

Solution

negative straight i with hat on top plus straight j with hat on top space minus 2 straight k with hat on top

a x b +c = 0
⇒ a x (a x b) + a x c = 0
⇒ (a.b)a-(a.a)b +a x c = 0
⇒ 3a - 2b + a x c = 0
⇒ 2b = 3a +a x c
$rightwards double arrow space 2 straight b space equals space 3 straight j with hat on top minus 3 straight k with hat on top space minus 2 straight i with hat on top space minus straight j with hat on top space minus straight k with hat on top space equals space minus 2 straight i with hat on top space plus space 2 straight j with hat on top space minus 4 straight k with hat on top rightwards double arrow space straight b space equals negative straight i with hat on top space plus straight j with hat on top minus 2 straight k with hat on top$

For Daily Free Study Material Join wiredfaculty

Vector Algebra

Some More Questions From Vector Algebra Chapter

The Boolean Expression (p∧~q)∨q∨(~p∧q) is equivalent to:

Mock Test Series

NCERT Sample Papers

Entrance Exams Preparation

Phone Number

Email Address

Location