5 Steps to a 5 AP Calculus BC 2019

Graphs of Functions and Derivatives 111

[−π,π] by [−2,2]

Figure 7.2-7

Using the [[ Zero] function of the calculator, you obtainx= 1 .25331 is a zero of f′on

0,

π

2

]

. Sincef′(x)=cos(x^2 ) is an even function,x=− 1 .25331 is also a zero on

[

−

π

2

,0

]

.

(See Figure 7.2-8.)

p –1.2533 1.2533

2

p

2

f′ –

f

+ –

[]

decr. incr. decr.

x

Figure 7.2-8

Thus,fis increasing on [− 1 .2533, 1.2533].

TIP • Bubble in the right grid. You have to be careful in filling in the bubbles especially when
you skip a question.

First Derivative Test and Second Derivative Test for Relative Extrema

First Derivative Test for Relative Extrema

Letf be a continuous function andcbe a critical number off. (Figure 7.2-9.)

Figure 7.2-9