
R(−1+2r,3−2r,−r)
dr′sofPRare(2−2r,−1+2r,−3+r)
Then, 2(2−2r)+2(1−2r)+1(3−r)=0
9−9r=0⇒r=1
R(1,1,−1)
then a+1=2,b+2=2,c−3=−2 i.e., a=1,b=0,c=1
∴a+b+c=2
JEE Main 2020 — Mathematics Vectors & 3D Geometry
If (a,b,c) is the image of the point (1,2,−3) in the line, 2x+1=−2y−3=−1z, then a+b+c is equal to:
Held on 5 Sept 2020 · Verified 6 Jul 2026.
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