Graph each function. Based on the graph, state the domain and the range and find any intercepts.

$$f(x)=\left\{\begin{array}{ll}{\ln x} & {\text { if } 0<x<1} \\ {-\ln x} & {\text { if } x \geq 1}\end{array}\right.$$

The reciprocal of a whole number is a fraction with __________ in the numerator.

Given matrices $A, B$, and $C$, multiply, if possible.

$$A=\left[\begin{array}{ll} 1 & 1 \\ 2 & 3 \end{array}\right] \quad B=\left[\begin{array}{rr} 3 & 2 \\ -1 & 1 \end{array}\right] \quad C=\left[\begin{array}{lll} 0 & 2 & 0 \\ 3 & 1 & 4 \end{array}\right]$$

CA

(a) Find the domain of each function. (b) Locate any intercepts. (c) Graph each function. (d) Based on the graph, find the range. (e) Is f continuous on its domain?

$$f(x)=\left\{\begin{array}{ll}{x^{2}} & {\text { if }-2 \leq x \leq 2} \\ {2 x-1} & {\text { if } x>2}\end{array}\right.$$

Graph each function. Based on the graph, state the domain and the range and find any intercepts.

$$f(x)=\left\{\begin{array}{ll}{\ln (-x)} & {\text { if } x \leq-1} \\ {-\ln (-x)} & {\text { if }-1<x<0}\end{array}\right.$$

Today is the first day of school and you are getting to know your teacher and classmates. Choose the phrase that you would use in each situation.

a. Comment ca va?

b. Comment tu t'appelles?

c. Comment il s'appelle?

d. Je m'appelle...

e. Bonjour,

Madame/Monsieur.

f. Elle s'appelle...

To introduce yourself

According to the Christian Science Monitor, 80 percent of egg cartons are imprinted with the logo "Animal Care Certified.."27 This designation means that the United Egg Producers, the egg industry's trade group, has certified egg producers according to internal guidelines.

What do you think the typical consumer interprets "Animal Care Certified" to mean?

Check Your Understanding Which of the following compounds would be soluble in water at room temperature?

(a) $\mathrm{NH}_4 \mathrm{Cl}$,

(b) $\mathrm{KOH}$,

(c) $\mathrm{Ca}\left(\mathrm{CH}_3 \mathrm{COO}\right)_2$,

(d) $\mathrm{Ba}_3\left(\mathrm{PO}_4\right)_2$

Circle the letter of the sentence in which the word in bold-faced type is used incorrectly.

a. In a monopoly, power is held on the basis of majority rule.

b. One student seems to monopolize every class discussion.

c. During the eighteenth century the British held an absolute monopoly on trade with the American colonies.

d. By gaining a monopoly in the steel industry, a few financiers virtually controlled the nation's economy.

A Mach number $M$ indicates the speed of a supersonic airplane. You can find an airplane's speed $a$ in miles per hour using the formula $a=M s$ where $s$ is the speed of sound at the altitude of the airplane. Find an airplane's speed in miles per hour if the airplane travels at Mach $2.5$ at an altitude where the speed of sound is $710 \mathrm{mi} / \mathrm{h}$. A. $177.5 \mathrm{mi} / \mathrm{h}$ B. $284 \mathrm{mi} / \mathrm{h}$ C. $1775 \mathrm{mi} / \mathrm{h}$ D. $2840 \mathrm{mi} / \mathrm{h}$

Graph each function. Based on the graph, state the domain and the range and find any intercepts.

$$f(x)=\left\{\begin{array}{ll}{-\ln x} & {\text { if } 0<x<1} \\ {\ln x} & {\text { if } x \geq 1}\end{array}\right.$$

Write the key term that best matches each description. Refer to the Terms to Know in the Summary & Study Guide on page 551.

doing business on the Internet

Find the reciprocal.

$$3 \frac{1}{2}$$

Given the following thermochemical equations,

$$\begin{array}{cc} \mathrm{CaO}(s)+\mathrm{Cl}_2(g) \longrightarrow \mathrm{CaOCl}_2(s) & \Delta H^{\circ}=-110.9 \mathrm{~kJ} \\ \mathrm{H}_2 \mathrm{O}(l)+\mathrm{CaOCl}_2(s)+2 \mathrm{NaBr}(s) \longrightarrow & 2 \mathrm{NaCl}(s)+\mathrm{Ca}(\mathrm{OH})_2(s)+\mathrm{Br}_2(l) \\ \Delta H^{\circ}=-60.2 \mathrm{~kJ} \\ \mathrm{Ca}(\mathrm{OH})_2(s) \longrightarrow H^{\circ}=+65.1 \mathrm{~kJ} \end{array}$$

calculate the value of $\Delta H^{\circ}$ (in kilojoules) for the reaction

$$\frac{1}{2} \mathrm{Cl}_2(g)+\mathrm{NaBr}(s) \longrightarrow \mathrm{NaCl}(s)+\frac{1}{2} \mathrm{Br}_2(l)$$