Question

If vector 2i+2j-2k, 5i+yj+k and -i+2j+2k are coplanar then the value of y is

Answer 1

this should be the ans bro

Answer 2

Answer:

The value of y is 23.

Explanation:

Let us considers a,b and c are vectors.

Given that,

$\vec{a}=2i+2j-2k$

$\vec{b}=5i+yj+k$

$\vec{c}=-i+2j+2k$

We know that,

Co-planar vector coordination is

$\vec{a}\cdot(\vec{b}\times\vec{c})=0$

$(2i+2j-2k)\cdot((5i+yj+k)\times(-i+2j+2k))=0$

$(2i+2j-2k)\cdot(i(2y-2)-11j+k(10+y))=0$

$4y-4-22-20-2y=0$

$2y=46$

$y= 23$

Hence, The value of y is 23.