Tardigrade
Tardigrade - CET NEET JEE Exam App
Exams
Login
Signup
Tardigrade
Question
Mathematics
If the distance of the point P (1,-2,1) from the plane x +2 y -2 z =α, where α>0, is 5 , then the foot of the perpendicular from P to the plane is
Q. If the distance of the point
P
(
1
,
−
2
,
1
)
from the plane
x
+
2
y
−
2
z
=
α
, where
α
>
0
, is
5
, then the foot of the perpendicular from
P
to the plane is
2246
224
JEE Advanced
JEE Advanced 2010
Report Error
A
(
3
8
,
3
4
,
−
3
7
)
B
(
3
4
,
−
3
4
,
3
1
)
C
(
3
1
,
3
2
,
3
10
)
D
(
3
2
,
−
3
1
,
2
5
)
Solution:
Distance of point
(
1
,
−
2
,
1
)
from plane
x
+
2
y
−
2
z
=
α
is
5
⇒
α
=
10
Equation of PQ
1
x
−
1
=
2
y
+
2
=
−
2
z
−
1
=
t
Q
≡
(
t
+
1
,
2
t
−
2
,
−
2
t
+
1
)
and
PQ
=
5
⇒
t
=
9
5
+
α
=
3
5
⇒
Q
≡
(
3
8
,
3
4
,
3
−
7
)