If are non–coplanar vectors, prove that the following vectors are non–coplanar :

and


Vectors parallel to the same plane, or lie on the same plane are called coplanar vectors

The three vectors are coplanar if one of them is expressible as a linear combination of the other two.


We have been given that, , and .


We can form a relation using these three vectors. Say,





Compare the vectors , and . We get


2 = x + y …(1)


–1 = x + y …(2)


3 = –2x – 3y …(3)


Solving equations (1) and (2) for x and y.


Equation (1), x + y = 2


Equation (2), x + y = –1


We get



The value of x and y cannot be found so it won’t satisfy equation (3).


Thus, , and are not coplanar.


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