We have to find the distance of the point (2, 1, 1) from the plane x - 2y + 4z + 8 = 0 As we know that, the distance between the point and the plane is given by |
Ax1+By1+Cz1−d
√A2+B2+C2
| Here, x1=2,y1=1 and z1=1 So, the distance of the given point form the given plane = |
1×2−2×1+4×1+8
√12+(−2)2+(4)2
| =|
12
√21
| So, the distance between the plane and the point is