The function g(x) = e ^( -x2 ) is continuous on ( -∞ ,∞ ) but its antiderivative is not an elementary function.
Letting t as a dummy variable of integration , we can write
∫0x [ d y / d t ] d t = ∫0x [ e ^( -t2 ) ] d t
y ( t ) | 0x = ∫0x [ e ^( -t2 ) ] d t
y (x) - y( 0 ) = ∫0x [ e ^( -t2 ) ] d t
y ( x ) - 1 = ∫0x [ e ^( -t2 ) ] d t
y ( x ) = 1 + ∫0x [ e ^( -t2 ) ] d t