Evaluate fracddxarctan(x)\\frac{d}{dx} \\arctan(x)fracddxarctan(x).
sec2(x)\\sec^2(x)sec2(x)
frac11+x2\\frac{1}{1+x^2}frac11+x2
frac1sqrt1−x2\\frac{1}{\\sqrt{1-x^2}}frac1sqrt1−x2
frac−11+x2\\frac{-1}{1+x^2}frac−11+x2