Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: [ap-calculus] Need help plaease on 2008 BC MC # 17
Replies: 1   Last Post: Sep 20, 2012 9:11 PM

 Doug Kuhlmann Posts: 3,630 Registered: 12/6/04
RE:[ap-calculus] Need help plaease on 2008 BC MC # 17
Posted: Sep 20, 2012 9:11 PM

NOTE:
This ap-calculus EDG will be closing in the next few weeks. Please sign up for the new AP Calculus
Teacher Community Forum at https://apcommunity.collegeboard.org/getting-started
and post messages there.
------------------------------------------------------------------------------------------------
The short answer is that h(x^2-3) is a compostion of functions. That is, it is h(g(x)) where g(x)=x^2-3.

If you wanted to indicate the product of h and x^2-3 then you would write it as h(x)*(x^2-3).

HTH

Doug
----------------------------
Doug Kühlmann
Math Dept
Andover, MA 01810

________________________________________
From: Qayumi, Enayat [eqayumi@tusd.net]
Sent: Thursday, September 20, 2012 1:18 PM
To: AP Calculus
Subject: [ap-calculus] Need help plaease on 2008 BC MC # 17

NOTE:
This ap-calculus EDG will be closing in the next few weeks. Please sign up for the new AP Calculus
Teacher Community Forum at https://apcommunity.collegeboard.org/getting-started
and post messages there.
------------------------------------------------------------------------------------------------
If h is a differentiable function and f(x) = h (x^2 - 3)

Why is the f'(x) = 2x h'(x^2-3) which will give the correct answer once you plug in x = 2

And Not

f'(x) = h' (x^2 - 3) + h (2x) due to the product rule? Once you find f'(2) = h' + 4h, it is not one of the MC options.

---
To search the list archives for previous posts go to