Book: Mathematics Part-II
Chapter: 11. Three Dimensional Geometry
Subject: Maths - Class 12th
Q. No. 13 of Exercise 11.3
Listen NCERT Audio Books - Kitabein Ab Bolengi
13
In the following cases, determine whether the given planes are parallel or perpendicular, and in case they are neither, find the angles between them.
4x + 8y + z – 8 = 0 and y + z – 4 = 0
The eq. of the given planes are
4x + 8y + z – 8 = 0 and y + z – 4 = 0
Two planes are ⊥ if the direction ratio of the normal to the plane is
a1a2 + b1b2 + c1c2 = 0
0 + 8 + 1
9 ≠ 0
∴ Both the planes are not ⊥ to each other.
Two planes are || to each other if the direction ratio of the normal to the plane is
∴ Both the planes are not || to each other.
The angle between them is given by
= 450
13
