1)

 If the line  r=(ˆi2ˆj+3ˆk)+λ(2ˆi+ˆj+2ˆk)    is parallel to the plane

r.(3ˆi2ˆj+mˆk)=10 , then the value of m is 


A) -2

B) 3

C) 2

D) -3

Answer:

Option A

Explanation:

Given line, 

           r=(ˆi2ˆj+3ˆk)+λ(2ˆi+ˆj+2ˆk)    is parallel to the plane

r.(3ˆi2ˆj+mˆk)=0

we know that, if line r= a+λ.b is parallel to plane  r.n=d

 then , b.n=0

     (2ˆi+ˆj+2ˆk).(3ˆi2ˆj+mˆk)=0

 6-2+2m=0

    m=-2