-->

Three Dimensional Geometry

Question
CBSEENMA12033432

Find the vector equation of the plane passing through the point A(2, 2, –1), B(3, 4, 2) and C (7, 0, 6). Also find the cartesian equation of the plane.

Solution

Here, straight a with rightwards arrow on top space equals space 2 space straight i with hat on top space plus space 2 space straight j with hat on top space minus space straight k with hat on top comma space space space space straight b with rightwards arrow on top space equals space 3 space straight i with hat on top space plus space 4 space straight j with hat on top space plus space 2 space straight k with hat on top comma space space straight c with rightwards arrow on top space equals space 7 space straight i with hat on top space plus space 6 space straight k with hat on top
The vector equations of plane is
         open parentheses straight r with rightwards arrow on top space minus space straight a with rightwards arrow on top close parentheses. space space space left parenthesis straight b with rightwards arrow on top space minus space straight a with rightwards arrow on top right parenthesis space cross times space left parenthesis straight c with rightwards arrow on top space minus space straight a with rightwards arrow on top right parenthesis space equals space 0
or          open square brackets straight r with rightwards arrow on top space minus space left parenthesis 2 space straight i with hat on top space plus space 2 space straight j with hat on top space minus space straight k with hat on top right parenthesis close square brackets. space space open square brackets left parenthesis straight i with hat on top space plus space 2 space straight j with hat on top space plus space 3 space straight k with hat on top right parenthesis space cross times left parenthesis 5 space straight i with hat on top space minus space 2 space straight j with hat on top space plus space 7 space straight k with hat on top right parenthesis close square brackets space equals space 0
The Cartesian equation of plane is
                open vertical bar table row cell straight x minus 2 end cell cell straight y minus 2 end cell cell straight z plus 1 end cell row 1 2 3 row 5 cell negative 2 end cell 7 end table close vertical bar space equals space 0
or      left parenthesis straight x minus 2 right parenthesis space open vertical bar table row 2 3 row cell negative 2 end cell 7 end table close vertical bar space minus space left parenthesis straight y minus 2 right parenthesis space open vertical bar table row 1 3 row 5 7 end table close vertical bar space plus space left parenthesis straight z plus 1 right parenthesis space open vertical bar table row 1 2 row 5 cell negative 2 end cell end table close vertical bar space equals space 0

or    (or – 2) (14 + 6) – (y – 2) (7 – 15) + (z + 1) (–2 – 10) = 0
or  20 (x – 2) + 8 (y – 2) – 12 (z + 1) = 0
or 5 (x – 2) + 2 (y – 2) – 3 (z + 1) = 0
or 5 x – 10 + 2y – 4 – 3 z – 3 = 0
or 5 x + 2 y – 3 z – 17 = 0

Some More Questions From Three Dimensional Geometry Chapter

Find the direction cosines of x, y and z-axis.