91Ó°ÊÓ

77–84 ? Factor the expression completely. Begin by factoring out the lowest power of each common factor. $$ x^{-3 / 2}+2 x^{-1 / 2}+x^{1 / 2} $$

\(77-82\) me Rationalize the denominator. $$ \frac{2}{\sqrt{2}+\sqrt{7}} $$

National Debt As of January 2001 , the population of the United States was \(2.83 \times 10^{8},\) and the national debt was \(5.736 \times 10^{12}\) dollars. How much was each person's share of the debt?

Limiting Behavior of Reciprocals Complete the tables. What happens to the size of the fraction 1\(/ x\) as \(x\) gets large? As \(x\) gets small?

\(77-82\) me Rationalize the denominator. $$ \frac{1}{\sqrt{x}+1} $$

77–84 ? Factor the expression completely. Begin by factoring out the lowest power of each common factor. $$ (x-1)^{7 / 2}-(x-1)^{3 / 2} $$

Number of Molecules A sealed room in a hospital, measuring 5 \(\mathrm{m}\) wide, 10 \(\mathrm{m}\) long, and 3 \(\mathrm{m}\) high, is filled with pure oxygen. One cubic meter contains 1000 \(\mathrm{L}\) , and 22.4 \(\mathrm{L}\) of any gas contains \(6.02 \times 10^{23}\) molecules (Avogadro's number). How many molecules of oxygen are there in the room?

77–84 ? Factor the expression completely. Begin by factoring out the lowest power of each common factor. $$ \left(x^{2}+1\right)^{1 / 2}+2\left(x^{2}+1\right)^{-1 / 2} $$

\(77-82\) me Rationalize the denominator. $$ \frac{y}{\sqrt{3}+\sqrt{y}} $$

77–84 ? Factor the expression completely. Begin by factoring out the lowest power of each common factor. $$ x^{-1 / 2}(x+1)^{1 / 2}+x^{1 / 2}(x+1)^{-1 / 2} $$