We are given the equation xy=yx. We will take the natural logarithm of both sides: ln(xy)=ln(yx) Using logarithm properties, we have:
yln(x)=xln(y) Now we differentiate both sides with respect to x using the product rule and implicit differentiation for terms involving y: dxd(yln(x))=dxd(xln(y)) dxdyln(x)+y⋅x1=1⋅ln(y)+x⋅y1dxdy dxdyln(x)+xy=ln(y)+yxdxdy Now we want to solve for dxdy, which we denote as y′. Rearrange the equation to isolate y′: y′ln(x)−yxy′=ln(y)−xy y′(ln(x)−yx)=ln(y)−xy y′=ln(x)−yxln(y)−xy We can multiply the numerator and denominator by xy: y′=xyln(x)−x2xyln(y)−y2