- #1
recoil33
- 28
- 0
I have a function which is:
y = 27x2 + 2100/x
dy/dx = 54x - 2100/x2
Critical points are for what x values, is y undefined or equal to 0?
Therefore, in this case i can only see the value of 0, which would cause the function to be undefined. Due to x2 being on the denominator.
EDIT:
0 = 54x - 2100/x2
0 = 54x3 - 2100
((-2100)/(54))(1/3) = x
x = - 3.38
Although I'm looking for the amount of positive values of x, which y = 0.
So therefore, 1?
Question: "How many critical numbers does y have, for positive x?"
Solved, 1.
Which solved my next question, it's a local minimum.
______________________________________________________________________________
Give the exact value of the x that minimises y for positive x.
Could someone explain what i am looking for? I don't really understand.
I think.
P' = 54x - 2100/x2
Once x hits -3.38 it minises y?
Which is in decimal, but i could convert to a whole number?
Thank you.
y = 27x2 + 2100/x
dy/dx = 54x - 2100/x2
Critical points are for what x values, is y undefined or equal to 0?
Therefore, in this case i can only see the value of 0, which would cause the function to be undefined. Due to x2 being on the denominator.
EDIT:
0 = 54x - 2100/x2
0 = 54x3 - 2100
((-2100)/(54))(1/3) = x
x = - 3.38
Although I'm looking for the amount of positive values of x, which y = 0.
So therefore, 1?
Question: "How many critical numbers does y have, for positive x?"
Solved, 1.
Which solved my next question, it's a local minimum.
______________________________________________________________________________
Give the exact value of the x that minimises y for positive x.
Could someone explain what i am looking for? I don't really understand.
I think.
P' = 54x - 2100/x2
Once x hits -3.38 it minises y?
Which is in decimal, but i could convert to a whole number?
Thank you.
Last edited: