What is the extreme f(x)=9x^3+21x^2+8x-3 ?

The extreme f(x)=9x^3+21x^2+8x-3 is Maximum(-4/3 , 7/3),Minimum(-2/9 ,-311/81)

Popular >

extreme f(x)=9x^3+21x^2+8x-3

extreme points

f (x) = 9 x^{3} + 21 x^{2} + 8 x - 3

Maximum (- \frac{4}{3}, \frac{7}{3}), Minimum (- \frac{2}{9}, - \frac{311}{81})

Solution steps

f^{'} (x) = 27 x^{2} + 42 x + 8

Find intervals:

Increasing

: - \infty < x < - \frac{4}{3},

Decreasing

: - \frac{4}{3} < x < - \frac{2}{9},

Increasing

: - \frac{2}{9} < x < \infty

Plug

x = - \frac{4}{3}

into

9 x^{3} + 21 x^{2} + 8 x - 3 : \frac{7}{3}

Maximum (- \frac{4}{3}, \frac{7}{3})

Plug

x = - \frac{2}{9}

into

9 x^{3} + 21 x^{2} + 8 x - 3 : - \frac{311}{81}

Minimum (- \frac{2}{9}, - \frac{311}{81})

Maximum (- \frac{4}{3}, \frac{7}{3}), Minimum (- \frac{2}{9}, - \frac{311}{81})

f (x) = x^{2} - 2 x + 5 [- 1.4]

2 x^{4} - 196 x^{2} - 3

f (x) = - x^{2} - y^{2} + 8 x + 8 y

f (x) = sin (3 x), - \frac{π}{4} \leq x \leq \frac{π}{3}

f (x, y) = x^{3} + 8 x^{2} y^{2} - 8 y^{3} - x + y

What is the extreme f(x)=9x^3+21x^2+8x-3 ?
The extreme f(x)=9x^3+21x^2+8x-3 is Maximum(-4/3 , 7/3),Minimum(-2/9 ,-311/81)