Why in 2nd question limit has not been checked along path y=mx while in 1st question limit has been checked along path y=mx.pls explain...if needed. pls mention

because we check at y = mx for checking limit (0,0) . but in second question - we are not checking limit at (0,0) , So not used y =mx

because we check at y = mx for checking limit (0,0) . but in second question - we are not checking limit at (0,0) , So not used y =mx