Well that is also wrong, or at least the .0 shows that the calculator is not doing the equations, it is just calculating. It doesn't know know that sqrt(2) x sqrt(2) = sqrt(2 x 2) = sqrt(2^2) = 2
And that is the kind of thing you get to understand if you do the calculations by hand.
And that is the kind of thing you get to understand if you do the calculations by hand.