The equation of the plane passing through a point with position vector i^+2j^+3k^ and parallel to the plane r→.(3i^+4j^+5k^)=0 is
3x+4y−5z+26=0
3x+4y+5z−26=0
3x−4y+5z−26=0
3x+4y−5z−26=0
Equation of the plane parallel to r¯.(3i¯+4j¯+5k¯)=0 is given by (xi¯+yj¯+zk¯)(3i¯+4j¯+5k¯)+λ=0
It passes through (1,2,3)
∴λ=−26