sqrt(1+x) - sqrt(x)

(FPCore (x) :precision binary64 (- (sqrt (+ 1.0 x)) (sqrt x)))

double code(double x) {
	return sqrt((1.0 + x)) - sqrt(x);
}

real(8) function code(x)
    real(8), intent (in) :: x
    code = sqrt((1.0d0 + x)) - sqrt(x)
end function

public static double code(double x) {
	return Math.sqrt((1.0 + x)) - Math.sqrt(x);
}

def code(x):
	return math.sqrt((1.0 + x)) - math.sqrt(x)

function code(x)
	return Float64(sqrt(Float64(1.0 + x)) - sqrt(x))
end

function tmp = code(x)
	tmp = sqrt((1.0 + x)) - sqrt(x);
end

code[x_] := N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]

\begin{array}{l}

\\
\sqrt{1 + x} - \sqrt{x}
\end{array}