AP Calculus
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Special Focus: The Fundamental<br />
Theorem of <strong>Calculus</strong><br />
Solutions<br />
1. (a) Using the FTC, the derivative of S(x) is the integrand evaluated at x:<br />
⎛ π x<br />
S '( x)<br />
= sin⎜<br />
⎝ 2<br />
2<br />
⎞<br />
⎟ .<br />
⎠<br />
(b) Technology produces the following graph of y = S"(x).<br />
Notice that the graph oscillates faster and faster as |x| increases. By using a<br />
calculator to find the zeros, students might recognize the numerical<br />
approximations for ± 2k . The zeros of S′<br />
( x) are 0,± 2,± 4, ± 6,....<br />
By hand, students can set S′ ( x) = 0 and continue in the following manner:<br />
⎛<br />
sin π x2 ⎞<br />
⎜ ⎟ = 0<br />
(Use the expression for S′<br />
( x).)<br />
⎝ 2 ⎠<br />
π x<br />
kπ<br />
2 = (Set the argument equal to kπ.)<br />
x<br />
2<br />
= ± 2 k<br />
(Solve for x.)<br />
x = 0, ± 2, ± 4, ± 6, ... (Let k = 0, 1, 2, 3, ....)<br />
116<br />
<strong>AP</strong>® <strong>Calculus</strong>: 2006–2007 Workshop Materials