91Ó°ÊÓ

Solve. Where appropriate, include approximations to three decimal places. $$ 3^{2 x}=81 $$

Classify each of the following statements as either true or false. The range of the function given by \(f(x)=\ln x\) is \((-\infty, \infty)\)

The percentage of smokers who receive telephone counseling and successfully quit smoking for \(t\) months is given by $$ P(t)=21.4(0.914)^{t} $$ Data: New England Journal of Medicine; California's Smoker's Hotline a) In what month will \(15 \%\) of those who quit and used telephone counseling still be smoke-free? b) In what month will \(5 \%\) of those who quit and used telephone counseling still be smoke-free?

Express as an equivalent expression that is a sum of logarithms. $$\log _{5}(25 \cdot 125)$$

Solve. Where appropriate, include approximations to three decimal places. $$ 2^{3 x}=64 $$

For pair of functions, find (a) \((f \circ g)(1)\) (b) \((g \circ f)(1) ;(\mathbf{c})(f \circ g)(x) ;(\mathbf{d})(g \circ f)(x)\). \(f(x)=x+4 ; g(x)=x^{2}-5\)

The net amount of e-book sales, in millions of dollars, can be estimated by $$ S(t)=2.05(1.8)^{t} $$ where \(t\) is the number of years after 2002 Data: Association of American Publishers a) In what year was there 8 billion dollars in e-book net sales? b) Find the doubling time.

Graph. $$ y=2^{x}+1 $$

For pair of functions, find (a) \((f \circ g)(1)\) (b) \((g \circ f)(1) ;(\mathbf{c})(f \circ g)(x) ;(\mathbf{d})(g \circ f)(x)\). \(f(x)=5 x+1 ; g(x)=2 x^{2}-7\)

Use a calculator to find each of the following to four decimal places. $$\log 7$$