What is the derivative of ln ((x^2 +1) /(2x))?

1 Answer
Jun 11, 2018

d/dx[ln(frac{x^2+1}{2x})] = frac{x^2-1}{x(x^2+1)}

Explanation:

Use the chain rule. Also, note that d/dx (lnx) = 1/x

d/dx[ln(frac{x^2+1}{2x})]

= frac{1}{(frac{x^2+1}{2x})} * frac{(2x)(2x)-(x^2+1)(2)}{(2x)^2}

= frac{2x}{x^2+1}*frac{4x^2 - 2x^2-2}{4x^2}

= frac{(2x)(2x^2-2)}{(4x^2)(x^2+1)}

= frac{4x(x^2-1)}{4x^2(x^2+1)}

= frac{x^2-1}{x(x^2+1)}