Thread: Derivative & Average Rate of Change

Let f(1)= 1/t for t>0. For what value of t is f '(t) equal to the average rate of change on f on [a,b]

A) -sqrt(ab) B) sqrt(ab) C) -1/(sqrt[ab]) D) 1/(sqrt[ab])
E) sqrt [(1/2)(1/b-1/a)]

Please Help

Originally Posted by rawkstar

Let f(1)= 1/t for t>0. For what value of t is f '(t) equal to the average rate of change on f on [a,b]

A) -sqrt(ab) B) sqrt(ab) C) -1/(sqrt[ab]) D) 1/(sqrt[ab])
E) sqrt [(1/2)(1/b-1/a)]

Please Help

I'm sure you meant










finish from here?

I don't know how you got from
to

Skeeter was merely writing the numerator as a single fraction,
to simplify further in your remaining steps, rawkstar.

(1/b)-(1/a)=(a/a)(1/b)-(b/b)(1/a)=a/(ab)-b/(ab)=(a-b)/(ab)

Originally Posted by rawkstar

I don't know how you got from
to

common denominator is ...





put them together ...

ok i think I got it, anyways the answer i got was B) sqrt(ab)