Practice COLLEGE ALGEBRA EXAM 1
Practice COLLEGE ALGEBRA EXAM 1
1. Simplify to an answer containing no negative exponents:
[((4xy-1)3)/((2x-2y)2 )].
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(4xy-1)3 (2x-2y)2
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= |
43 x3 (y-1)3 22(x-2)2y2
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= |
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43 x3 y-1 ·3 4x-2 ·2y2
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= |
42 x3 y-3 x-4y2
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= |
42 x3x4 y3 y2
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= |
42 x7 y5
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. |
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2. Extract squares: Ö[(4(x + 1)2)].
Extract cubes: Ö[3]8(x + 1)3.
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| _______ Ö4(x + 1)2
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= 2|x+1|, |
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because nonnegativity is implicit in even radical symbol. |
| | Ö[3]8(x + 1)2 = 2(x+1), because odd roots are unique. |
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3. Solve: x2 = x4.
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x4 - x2 = 0 Þ x2(x+1)(x-1) = 0. |
| | x = 0 or x = 1 or x = -1. |
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4. Find the domain of: Ö[(x + 5 )] -[1/(x - 1)] .
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No even rooting negative Þ x+ 5 ³ 0. |
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No division by 0 Þ x \not = 1. |
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5. A paints 1 room in 2 days. B paints 1 room in 5 days.
If they work together, how many days does it take them to paint in 5 rooms?
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(x days ) |
æ ç
è
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1 room 2 days
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+ |
1 room 5 days
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ö ÷
ø
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= 5 rooms . |
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6. Reduce: [(4 - x2)/(x2 - 4x + 4)] .
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4 - x2 x2 - 4x + 4
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= |
(2-x)(2+x) (x-2)(x-2)
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= - |
x +2 x-2
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. |
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7. Factor into irreducible factors: 7(x2 - 2x + 1) - 3(x-1).
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7(x2 - 2x + 1) - 3(x-1) = 7(x-1)(x-1) - 3(x-1) = |
| | (7(x-1) - 3)(x-1) = (7x - 10)(x-1). |
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8. Find the quotient and remainder (x4 + 2) ¸(3x3 - 1).
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(x4 + 2)- ( |
1 3
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x (3x3 - 1)) = |
1 3
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x + 2 = Remainder. |
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9. Write the product (x-2)2(x+2)2 as a polynomial in standard form.
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(x-2)2(x+2)2 = (x-2)(x+2)(x-2)(x+2) = |
| | (x2 - 4) (x2 - 4) = x4 - 8x2 + 16. |
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10. Solve for the exact answer:
Ö3(x + 2) + 1 = 2 x - Ö2.
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Isolate: Ö3 x - 2x = - 2 Ö3 - Ö2 -1. |
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Factor: (Ö3 - 2)x = - 2 Ö3 - Ö2 -1 . |
| | x = |
- 2 Ö3 - Ö2 -1 Ö3 - 2
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. |
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On 28 Jan 2001, 15:23.