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The reflection of the point (2,-1,-3) in the plane 3x - 2y -z = 9 is : |
Answer» line AB=`(x-2)/3=(y+1)/-2=(z-3)/-1=lambda` `(x,y,z)=(3lambda+2,-2lambda-1,-lambda+3)` `3x-2y-z=9` `3(3lambda+2)-2(-2lambda-1)-3+lambda=9` `9lambda+6+4lambda+2-3+lambda=9` `14lambda=4` `lambda=2/7` `C(x,y,z)=(20/7,-11/7,19/7)` A(2,-1,3) C is MP of A and B `C=(A+B)/2, B=(2C-A)` `B=(26/7,-22/7+1,38/7-3)` `B=(26/7,-15/7,17/7)` option b is correct. |
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