Let me separate it out, this wasn't part, this wasn't part of this original expression right over here, but using this initial condition. So it tells us when x is zero, y needs to be equal to one. So we would have one squared, which is just one, over two is equal to one half, e to the negative zero squared, well that's just going to be, e to the zero is just one, so it's going to be one half plus c, and just like that, we're able to figure out if you subtract one half from both sides, c is equal to zero. So the relationship between y and x that goes through this point, we could just set c is equal to zero, so that's equal to zero, that's zero right over there, and so we are left with y squared over two is equal to e to the negative x squared over two. Now we can multiply both sides by two, and we're going to get y squared, y squared, let me do that, so we're going to get y squared is equal to, is equal to e to the negative x squared. Now we can take the square root of both sides, and you could say, well look, y squared is equal to this, so y could be equal to the plus or minus square root of e to the negative x squared, of e to the negative x squared, but they gave us an initial condition where y is actually positive. So we're finding the particular solution that goes through this point, that means y is going to be the positive square root.