RBSE Solutions for Class 12 Maths Chapter 14 Three Dimensional Geometry Ex 14.7
RBSE Solutions for Class 12 Maths Chapter 14 Three Dimensional Geometry Ex 14.7
Rajasthan Board RBSE Class 12 Maths Chapter 14 Three Dimensional Geometry Ex 14.7
Question 1.
Find the angle between the planes :
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Solution:
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Question 2.
Find the angle between the planes :
(i) x + y + 2z = 9 and 2x – y + z = 15
(ii) 2 x – y + z = 4 and x + y + 2z = 3
(iii) x + y – 2z = 3 and 2x – 2y + z = 5
Solution:
If plane are a1x + b1y + c1z + d1 = 0 and a2x + b2y + c2z + d2 = 0 then angle between them is
Question 3.
Show that following planes are at right angles :
Solution:
x – 2y + 4z = 10 and 18x + 17y + 4z = 49
a1 = 1,b1 = -2, c1 = 4 and a2 = 18 b2 = 17, c2 = 4
(i) Planes will be perpendicular if
a1 a2 + b1b2 + c1c2 = 0
L.H.S. = 1 × 18 + (-2) × 17 + 4 × 4
= 18 – 34+16
= – 34 + 34
= 0
∴ L.H.S. = R.H.S.
Question 4.
Find λ, if following planes are perpendicular to each other:
Solution:
Question 5.
Find the angle between the line x+1/ 3 = y−1/ 2 = z−2/ 4 and the plane 2x + y – 3z + 4 = 0
Solution:
Normal vector of the plane 2x + y – 3z + 4 = 0
Question 6.
Find the ngle between the line x−23 = y+1−1 = z−32 and the plane 3x + 4y + z + 5 = 0.
Solution:
Question 7.
Find the angle between
Solution:
We know that the angle between the line and the plane is
Question 8.
Find the angle between
Solution:
We know that angle between the line
Question 9.
Determine the value of m, if line
Solution:
Question 10.
Find m, if line
is parallel to the plane
Solution:
If given line is parallel to given plane