Three Dimensional Geometry - Online Test

Q1. The equation of a plane through a point whose position vector is     and perpendicular to the vector    . is
Answer : Option C
Explaination / Solution:

In vector form The equation of a plane through a point whose position vector is    and perpendicular to the vector   . Is given by : 

Q2. Equation of a plane passing through three non collinear points (x1, y1, z1),(x2, y2, z2) and (x3, y3, z3) is
Answer : Option D
Explaination / Solution:

In cartesian co – ordinate system : Equation of a plane passing through three non collinear points (x1, y1, z1),(x2, y2, z2) and (x3, y3, z3) is given by : 

Q3. Vector equation of a plane that contains three non collinear points having position vectors  is
Answer : Option D
Explaination / Solution:

Vector equation of a plane that contains three non collinear points having position vectors  is given by: 

Q4. Equation of a plane that cuts the coordinates axes at (a, 0, 0), (0, b, 0) and (0, 0, c) is
Answer : Option D
Explaination / Solution:

Equation of a plane that cuts the coordinates axes at (a, 0, 0), (0, b, 0) and (0, 0, c) is called the equation of plane in intercept form having intercepts a , b , and c on coordinate axis i.e. at x- axis , y – axis and z – axis respectively is given by : .

Q5. Vector equation of a plane that passes through the intersection of planes  expressed in terms of a non – zero constant  is
Answer : Option C
Explaination / Solution:

Vector equation of a plane that passes through the intersection of planes  expressed in terms of a non – zero constant  is given by: 

Q6. Two lines  are coplanar if
Answer : Option D
Explaination / Solution:

In vector form:
Two lines  are coplanar if (
.
Q7. In the Cartesian form two linesand are coplanar if
Answer : Option D
Explaination / Solution:

In the Cartesian form two linesand are coplanar if


Q8. In vector form, if  is the angle between the two planes  then
Answer : Option B
Explaination / Solution:

In vector form, if  is the angle between the two planes  then, cosine of the angle between these two lines is given by :  

Q9. Find the equation of the plane through the line of intersection of the planes x + y + z = 1 and 2x + 3y + 4z = 5 which is perpendicular to the plane x – y + z = 0.
Answer : Option D
Explaination / Solution:

The equation of the plane through the line of intersection of the planes 


Q10. Find the angle between the planes whose vector equations are 
Answer : Option A
Explaination / Solution: