Question

Find the absolute maximum and absolute minimum values of f(x)= x^3 - 6x^2 +9x -3 on interval [-1,2
]

Answer 1

f(x)= x^3 - 6x^2 +9x -3
derivate:
3x^2 - (2)x + 9
set it equal to zero
0=3x^2 - (2)x + 9
solve for x

Answer 2

what he said ,lol

Answer 3

i did that and got 3(x-3)(x-1) but then what

Answer 4

my mistake
derivative is:
3x^2 - (2)(6)x + 9

(forgot the 6)

Answer 5

ya, good
so what are your roots then

Answer 6

well what i did was for the deriv. i got 3x^2 -12x +9. and set it equal to zero to get 3(x-3)(x-1). I believe i should set the (x-3) and (x-1) to zero but i cant remembe rwhat to do with the 3 in the front

Answer 7

you don't need to worry about the 3 infront, just do,
0=x-3
0=x-1

Answer 8

ohhhhh okay thank you :)

Answer 9

yep ^_^