extreme f(x)=x^2-18ln(x)

解答

极值点

f (x) = x^{2} - 18 ln (x)

极小值 (3, 9 - 18 ln (3))

求解步骤

f^{'} (x) = 2 x - \frac{18}{x}

Find intervals:

递减

: 0 < x < 3,

递增

: 3 < x < \infty

将

x = 3

代入

x^{2} - 18 ln (x) : 9 - 18 ln (3)

极小值 (3, 9 - 18 ln (3))

e x t re m e f (x) = 4 cos (2 x) + 1

e x t re m e f (x) = 7 x - 7 sin (x), 0 \leq x \leq 2 π

e x t re m e f (x) = 7 x y - λ (6 x + 11 y - 2)

e x t re m e x^{2} - 20 x + 150

e x t re m e f (x) = x^{20} + 4 x^{10} + 8