1. ## Differentiation

Sorry for the bother but the book doesn't have an example for these questions, I understand how to do the questions further on and I think these use the same principle but these are really frustrating me and I can't figure them out. I can differentiate and find the co-ordinates of stationary points on a curve and decide whether they are maximum, miminum, or points of inflexion. Once again sorry for being annoying.

Exercise 9B

1. Find the least value of each of the following functions:

a) f(x) = x^2 - 12x + 8

(not sure how to type powers so I just put ^2)

If someone could just tell me the method, I can figure it out for the rest.

Thank you.

2. Originally Posted by Jack Shannon
Sorry for the bother but the book doesn't have an example for these questions, I understand how to do the questions further on and I think these use the same principle but these are really frustrating me and I can't figure them out. I can differentiate and find the co-ordinates of stationary points on a curve and decide whether they are maximum, miminum, or points of inflexion. Once again sorry for being annoying.

Exercise 9B

1. Find the least value of each of the following functions:

a) f(x) = x^2 - 12x + 8

(not sure how to type powers so I just put ^2)

If someone could just tell me the method, I can figure it out for the rest.

Thank you.
the least value, aka, the minimum value occurs at the vertex. this happens where the slope is zero.

find the derivative, set it equal to zero and solve for x

the corresponding y-value is the least value you are after

3. Thank you very much, I understand now, say I wanted to find the Greatest value of a function, would I still use the y value?

4. Originally Posted by Jack Shannon
Thank you very much, I understand now, say I wanted to find the Greatest value of a function, would I still use the y value?
yes.

that would not happen here though. we have a greatest value when we have a downward opening parabola