(The function is cubed) How do you find a and b?
f(x)=3(ax-b/x)^3
Given f (3/2) = 3
and f' (3/2) = 30
Given
and
2 Answers
Explanation:
Since
we get:
that's
Since
we get
that's
Let's substitute
that's
Since
and we'll substitute it in
The we get:
Since
Please see below.
Explanation:
We are given:
Using the definition of
So
Clear fractions by multiplying by
We are also given some information about the derivative of
we find the derivative:
f'(x) = 9(ax-b/x)^2(a+b/x^2)
Using
= 9(3/2a-2/3b)^2(a+4/9b)
= (3/2a-2/3b)^2(9a+4b)
Recall from above that the first factor is
Solving the system
We get