critical f(x,y)=4x^4+4y^4-2xy

解答

临界点

f (x, y) = 4 x^{4} + 4 y^{4} - 2 x y

(0, 0), (- \frac{1}{2 2}, - \frac{1}{2 2}), (\frac{1}{2 2}, \frac{1}{2 2})

求解步骤

4 x^{4} + 4 y^{4} - 2 x y

找到

\nabla f (x, y)

等于零或无定义的点

(0, 0), (- \frac{1}{2 2}, - \frac{1}{2 2}), (\frac{1}{2 2}, \frac{1}{2 2})

cr i t i c a l f (x) = (x^{2} - 3) e^{- x}

cr i t i c a l f (x) = - 2 x^{3} + 33 x^{2} - 108 x + 11

cr i t i c a l f (x) = x y + \frac{2}{x} + \frac{4}{y}

cr i t i c a l f (x) = cos (\frac{2 π}{3} x)

cr i t i c a l f (x) = - 3 x^{4} + 20 x^{3} - 17