題目 Problem Find the saddle point of the function f(x,y)=x3−y2−xy+1.f(x,y)=x^3-y^2-xy+1.f(x,y)=x3−y2−xy+1. (a) (0,0)(0,0)(0,0) (b) (−16,112)\left(-\frac16,\frac1{12}\right)(−61,121) (c) (16,−112)\left(\frac16,-\frac1{12}\right)(61,−121) (d) Does not exist. (e) None of the above. 解答 待補。
