CHAPTER 5 Review Exercises^353
Write each boldface italic number in scientific notation.
40.An electron and a positron attract each other in two ways: the electromagnetic attraction
of their opposite electric charges, and the gravitational attraction of their two masses. The
electromagnetic attraction is
4,200,000,000,000,000,000,000,000,000,000,000,000,000,000
times as strong as the gravitational. (Asimov, Isaac, Isaac Asimov’s Book of Facts.)
41.The aircraft carrier USS John Stennis is a 97,000-ton nuclear powered floating city with a
crew of 5000.(Source:Seelye, Katharine Q., “Staunch Allies Hard to Beat: Defense
Dept., Hollywood,” New York Times,in Plain Dealer.)
42.A googol is
10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000.The Web search engine Google is named after a googol. Sergey Brin, president and
cofounder of Google, Inc., was a mathematics major. He chose the name Google to describe
the vast reach of this search engine. (Source: The Gazette.)
43.According to Campbell, Mitchell, and Reece in
Biology Concepts and Connections(Benjamin Cum-
mings, 1994, p. 230), “The amount of DNA in a hu-
man cell is about 1000 times greater than the DNA in
E. coli.Does this mean humans have 1000 times as
many genes as the 2000 in E. coli? The answer is
probably no; the human genome is thought to carry
between 50,000and 100,000genes, which code for
various proteins (as well as for tRNA and rRNA).”5.4 In Exercises 44– 48, combine like terms where possible in each polynomial. Write the
answer in descending powers of the variable. Give the degree of the answer. Identify the
polynomial as a monomial,a binomial,a trinomial,or none of these.
49.Simplify.
Add or subtract as indicated.15 x^3 y^2 - 3 xy^5 + 12 x^22 - 1 - 9 x^2 - 8 x^3 y^2 + 2 xy^52112 r^4 - 7 r^3 + 2 r^22 - 15 r^4 - 3 r^3 + 2 r^2 - 1212 a^5 - 9 a^4 + 8 a^3 + 2 a^2 - a+ 3 - 7 y^5 - 8 y^4 - y^5 +y^4 + 9 y9 m^2 + 11 m^2 + 2 m^2 - 4 p+p^3 - p^2 + 8 p+ 250.Add. 51.Subtract. 52.Subtract.k^4 + 7 k^2 - 11 k- 12 k^4 - 8 k^2 + 7 k
5 y^2 + 2 y- 7
6 y^2 - 8 y+ 2
3 a^3 - a^2- 2 a^3 + 5 a^2
Graph each equation by completing the table of values.
53.y=-x^2 + 5 54.y= 3 x^2 - 2
x 012
y- 2 - 1 x 01 2
y- 2 - 1
5.5 Find each product.
55. 56.
57. 58.
59. 60.
- 16 k+ 5 q 212 k- 7 q 2 62. 1 s- 123
13 k- 6212 k+ 12 1 a+ 3 b 212 a-b 215 p^2 + 3 p 21 p^3 - p^2 + 52 1 m- 921 m+ 221 a+ 221 a^2 - 4 a+ 12 13 r- 2212 r^2 + 4 r- 32