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Recent problems solved by 'edjones'
edjones answered: 7568 problems
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(1 pt) Let the function f be defined by f(x) = {1}/{sqrt{1-x^2}}. Indicate whether the following statements are True (T) or False (F). You must get all answers correct in order to receive credit.
___1. f(x) is never positive.
___2. 1 is in the domain of f
___3. 0 is in the domain of f
___4. f(x) is never negative.
___5. All negative real numbers are in the domain of f
___6. f(x) is never zero.
___7. All positive real numbers are in the domain of f
1 solutions
Answer 248523 by edjones(7569)   on 2010-09-24 15:15:45 (Show Source):
You can put this solution on YOUR website!f(x)=1/sqrt(1-x^2)
.
2.
1-x^2>0 If it is zero then there is division by zero which is not allowed. If it is less than zero then the denominator is an imaginary number, also not allowed.
-x^2>-1
x^2<1
2 is F
.
The rest of your answers are correct.
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Ed
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Geometry_Word_Problems/347668: Suppose there are two cubes, with the first cube having a side of h, and the second cube having a side of 5h. What is the relation of the volume of the first cube to the volume of the second?
1 solutions
Answer 248510 by edjones(7569) on 2010-09-24 14:06:57 (Show Source):
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Miscellaneous_Word_Problems/347313: If the sides of a square are lengthened by 6cm, the area becomes 121cm^2. find the length of a side of the original square
The length of a side of the original square is _?_cm
1 solutions
Answer 248342 by edjones(7569) on 2010-09-23 18:00:18 (Show Source):
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Functions/347302: Hi, Im doing functions, and im just STUCK! Were supposted to plug in 9, but then what? thanks!
f(x)=7x+-15;f=9
1 solutions
Answer 248338 by edjones(7569) on 2010-09-23 17:54:54 (Show Source):
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Probability-and-statistics/347038: 5. The Centers for Disease Control have determined that when a person is given a vaccine, the probability that the person will develop immunity to a virus is 0.8. If 7 people are given this vaccine, find the probability that
a. at least five will develop immunity
b. exactly four will develop immunity
c. all will develop immunity
1 solutions
Answer 248147 by edjones(7569) on 2010-09-23 01:18:32 (Show Source):
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Linear_Equations_And_Systems_Word_Problems/347044: 1. If 2/3 of employees of a company are women and 1/4 of the remaining employees are married and the rest are 9 bachelors. What is the total number of employees?
2. How would you divide $40 between two student in the ratio of 3 is to 5?
3. Ice placed in an ice box 15% of its weight before being used. How many tons of ice must be placed in an ice boxes so as to have 850 tons for use?
1 solutions
Answer 248146 by edjones(7569) on 2010-09-23 01:02:44 (Show Source):
You can put this solution on YOUR website!Let x be the total number of employees.
2x/3 + (x/3 * 1/4) + 9 = x
2x/3 + x/12 + 9 = x
8x+x+108=12x multiply each side by 12.
-3x=-108
x=36
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Ed
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Length-and-distance/347010: Find the distance between the pair of points.
(3 sqrt(13), -2) and (4 sqrt(13), 4)
Answer choices:
A. 7
B. 49
C. 49/2
D. 6
*I tried using the distance formula but never came up with one of the answer choices given. Please help and clear things up! Thanks :)
1 solutions
Answer 248141 by edjones(7569) on 2010-09-23 00:35:43 (Show Source):
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Miscellaneous_Word_Problems/347015: With water from one hose, a swimming pool can be filled in 8 hours. A second, larger hose used alone can fill the pool in 5 hours. How long would it take to fill the pool if both hoses were used simultaneously?
1 solutions
Answer 248139 by edjones(7569) on 2010-09-23 00:23:43 (Show Source):
You can put this solution on YOUR website!Larger hose fills 1/5 the pool in 1 hr. Smaller hose fills 1/8 the pool in 1 hr.
1/8 + 1/5
= 5/40 + 8/40
=13/40 of the pool filled in 1 hr.
40/13= hrs to fill the pool.
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Ed
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Probability-and-statistics/347018: A three digit number is chosen at random. What is the probability that either all the digits are odd or all the digits are even? Assume the first digit is not zero and that zero is even.
1 solutions
Answer 248138 by edjones(7569) on 2010-09-22 23:56:47 (Show Source):
You can put this solution on YOUR website!If the 1st digit is odd then 1/2 * 1/2 = 1/4 all odd.
If the 1st digit is even then 1/2 * 1/2 = 1/4 all even.
Since the 1st digit must be either odd or even but not both then 1/4 is the probability that either all the digits are odd or all the digits are even.
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Angles/347019: Angle L and angle M are complementary angles.Angle N and angle P are complementary angles.If angle L=y-2, angle M=2x+3, angle N=2x-y, and angle P=x-1, find the values of x, y, angle L, angle M, angle N, and angle P.
1 solutions
Answer 248137 by edjones(7569) on 2010-09-22 23:47:00 (Show Source):
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Linear_Equations_And_Systems_Word_Problems/347021: what multiplier should be used for each of the following equations to eliminate one unknown by subtraction? 3x-y=7, 2x+7y=42.
A.)7 for the first equation, 1 for the second
B.)6 for the first equation, 7 for the second
C.)3 for the first equation, 2 for the second
D.)2 for the first equation, 3 for the second
1 solutions
Answer 248136 by edjones(7569) on 2010-09-22 23:33:04 (Show Source):
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absolute-value/347026: if the values of the expressions -11, -1, 9, and 17 are plotted on a number line, which expression would be furthest from 8.
1 solutions
Answer 248134 by edjones(7569) on 2010-09-22 23:26:26 (Show Source):
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Probability-and-statistics/346564: 1.Some students were asked if they carry a credit card. Here are the responses.
Class Credit Card Carrier Not a Credit Card Carrier Total
Freshman 33 27 60
Sophomore 6 34 40
Total 39 61 100
What is the probability that the student is a sophomore and doesn't carry a credit card?
2.Some students were asked if they carry a credit card. Here are the responses.
Class Credit Card Carrier Not a Credit Card Carrier Total
Freshman 33 27 60
Sophomore 6 34 40
Total 39 61 100
What is the probability that the student is a sophomore given he doesn't carry a credit card?
1 solutions
Answer 247847 by edjones(7569) on 2010-09-22 11:05:09 (Show Source):
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Probability-and-statistics/346633: A student takes a multiple choice test with 10 questions (four answers per question) and guesses at each of the ten. The probability that he gets at least half right?
1 solutions
Answer 247832 by edjones(7569) on 2010-09-22 10:35:31 (Show Source):
You can put this solution on YOUR website!Expand the binomial (a+b)^10 Let a=.75 and b=.25
a^10=.0563 all wrong
10a^9b=.1877
45a^8b^2=.2816
120a^7b^3=.2503
210a^6b^4=.1460 six wrong
==========>.9219
.
1-.9219=.0781 The probability that he gets at least half right.
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Ed
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Permutations/346405: Four wires (red, green, blue, and yellow) need to be attaches to a circuit board. a robotic device will attach the wires. the wires can be attached in any order, and the production manager wishes to determine which order would be fastest for the robot to use. Determine the number of all the posible sequences of assembly that must be tested.
1 solutions
Answer 247686 by edjones(7569) on 2010-09-21 20:00:52 (Show Source):
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