my problem I am working on is f(x)= x+(54/x); [6,9]
First I took the first derivative and found that it was f ' (x)= 1-(54/x^2)
I then found f(6) = 15 and f(9) = 15
If I plug those into the formula f(b)-f(a) I get 0 this just doesn't make
This just doesn't make sense!! Could someone help me?