dxd(xx+xa+ax+aa)=dxd(xx)+dxd(xa)+dxd(ax)+dxd(aa)=dxd(y)+axa−1+axloga+0 ...(i) y=xx[letxx=y] Taking log on both sides, logy=xlogx On differentiating w.r.t. x, we get y1dxdy=x×x1+logx ⇒ dxdy=xx(1+logx) Substitute the value of dxdy in Eq. (i), dxd(xx+xa+ax+aa)=xx(1+logx)+axa−1+axloga