The distance of the point (2,1,-1) from the plane `x-2y+4z=9` is (A) `sqrt(13)/21` (B) `13/21` (C) `13/sqrt(21)` (D) `sqrt(13/21)`

The distance of the point P(1,-3) from the line 2y-3x=4 is (A) 13 (B) (7)/(13)sqrt(3) (C) sqrt(13) (D) (7)/(13)

The inverse of the matrix [(2,1),(1,3)] is

The inverse of the matrix ([2,1],[1,3]) is

If A(1,-1,2),B(2,1,-1)C(3,-1,2) are the vertices of a triangle then the area of triangle ABC is (A) sqrt(12) (B) sqrt(3) (C) sqrt(5) (D) sqrt(13)

The distance of (0,0) from 2x-3y+5=0 measured parallel to the line 3x-2y=1=0 is (5)/(sqrt(13)) b.(4)/(sqrt(13)) c.sqrt(13) d.none of these

The distance of (0,0) from 2x-3y+5=0 measured parallel to the line 3x-2y=1=0 is 5/(sqrt(13)) b. 4/(sqrt(13)) c. sqrt(13) d. none of these

Subtract the following: 21/15 from 13/12

Distance between parallel lines 4x+6y+8=0, 6x+9y+15=0 is (i) 2/sqrt13 (ii) 1/sqrt13 (iii) 3/sqrt13 (iv) 4/sqrt13

(1)/(sqrt(21+4x-x^(2)))