Question

Find the critical points (min. max.) & points of inflection of

y = 1/3³ - 1/2x² - 2x

Someone help me please? : )

Answer 1

is that 1/3x^3 or is 1/3^3

Answer 2

1/3x

Answer 3

Sorry typo :D

Answer 4

1/3x³

Answer 5

finding x
u deferentiate
this gives x^2-x-2=0(this is ur y')
x=2 or x=-1
sub x into the original equation
y=-13/3 or y=13/6
def y'' to get inflection

Answer 6

kirstinpearl: a word of advice - the way you've typed the question is confusing - 1/3x^3 can mean 'one third times x cubed' or 'one divided by 3 x cubed'.
it is better to use the equation generator or draw function
If you are not happy with these then type one third x cubed as (1/3)x^3 to avoid confusion.
if the first option is correct, then remainder has solved it for you.

Answer 7

y" = 2x-1
for x = 2, y" is positive so (2,-13/3) is a minimum
for x = -1, y" is negative so (-1,13/6) is a maximum