Page 27 - Schaum's Outline of Theory and Problems of Applied Physics

12 USEFUL MATH [CHAP. 1

1.9. A square foot contains approximately
(a) 144 cm 2 (c) 929 cm 2
(b) 366 cm 2 (d) 1000 cm 2

1.10. A week contains approximately
4
5
(a)1.0 × 10 s (c)6.05 × 10 s
4
6
(b)6.05 × 10 s (d)2.6 × 10 s

Supplementary Problems

1.1. Remove the parentheses from the following, and combine like terms:
(a) a + (b + c − d) (f) b − 3(b + 3)
(b) a − (b + c − d) (g)2a − 3b − 4(a − 2b)
(c) a + 2(b − 4) (h)3(a + b) − 3(a + 2b)
(d) a − 2(b − 4) (i)2(a + b) − 3(a − b) + 4(a + 2b − c)
(e) b + 3(b + 3) (j)5(a + b + c) − 5(a − b − c)

1.2. Evaluate the following:
3(x + y)
(a) when x = 5 and y =−2
2
1 1
(b) − when x = 3 and y = 2
x − y x + y
4xy
(c) + 5 when x = 1 and y =−2
y + 3x
x + y z
(d) + when x =−2, y = 2, and z = 4
2z x − y
x + z xy
(e) − when x = 2, y = 8, and z = 10
y 2
3(x + 7)
(f) when x = 3 and y =−6
y + 2
5(3 − x)
(g) when x =−5 and y = 7
2(x + y)
2
x + y 2 z
(h) + when x =−2, y = 2, and z = 4
2z x − y
(x + z) 2 xy
(i) − when x = 2, y = 8, and z = 10
y 2
1.3. Solve each of the following equations for x:
4x − 35 (d) 2x − 32 = 0 x + y
4
(a) = 9(1 − x) (h) z =
3 (e) 3x = 6x x − y
2
3x − 42 (f) (x + 3)(x − y) = z + x 2 x 4
2
(b) = 2(7 − x) √ (i) =
9 y z
(g) y 2x = 12
3
(c) x + 27 = 0