Let the image of the point P(2,−1,3) in the plane x+2y−z=0 be Q. Then the distance of the plane 3x+2y+z+29=0 from the point Q is
Explanation
Solution
Step 1: Find the Coordinates of Point Q.
Using the image formula ax−x1=by−y1=cz−z1=a2+b2+c2−2(ax1+by1+cz1+d):
1x−2=2y+1=−1z−3=12+22+(−1)2−2(2+2(−1)−3)=6−2(−3)=1.
x−2=1⟹x=3; y+1=2⟹y=1; z−3=−1⟹z=2.
So, Q=(3,1,2).
Step 2: Find Distance from Q to the Second Plane.
Plane: 3x+2y+z+29=0.
d=32+22+12∣3(3)+2(1)+2+29∣=14∣9+2+2+29∣=1442.
1442=143×14=314.
Correct Option: (3)
Explanation
Solution
Step 1: Find the Coordinates of Point Q.
Using the image formula ax−x1=by−y1=cz−z1=a2+b2+c2−2(ax1+by1+cz1+d):
1x−2=2y+1=−1z−3=12+22+(−1)2−2(2+2(−1)−3)=6−2(−3)=1.
x−2=1⟹x=3; y+1=2⟹y=1; z−3=−1⟹z=2.
So, Q=(3,1,2).
Step 2: Find Distance from Q to the Second Plane.
Plane: 3x+2y+z+29=0.
d=32+22+12∣3(3)+2(1)+2+29∣=14∣9+2+2+29∣=1442.
1442=143×14=314.
Correct Option: (3)