Choose the correct option if a1 x + b1 y + c1 z + d = 0 and a2 x + b2 y + c2 z + d = 0 are two planes where a1, b1, c1 and a2, b2, c2 are the direction ratios of normal to the planes –
1
These two planes are perpendicular if and only if a1⋅ a2 + b1 ⋅ b2 + c1 ⋅ c2 = 0
2
These two planes coincides if and only \(\frac{{{a_1}}}{{{a_2}}} = \frac{{{b_1}}}{{{b_2}}} = \frac{{{c_1}}}{{{c_2}}}\)
3
The angle between these planes will be equal to the acute angle between normal vectors of the plane.
4
All of the above