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13410..13439 , 13440..13469 , 13470..13499 , 13500..13529 , 13530..13559 , 13560..13589 , 13590..13619 , 13620..13649 , 13650..13679 , 13680..13709 , 13710..13739 , 13740..13769 , 13770..13799 , 13800..13829, >>NextExponential-and-logarithmic-functions/317239: Please Show work:
Subtract:
4/6(x-1) - 3/6(x-1)
would this be 1/6(x-1)? (4-1)/6(x-1)
or could it simply be 1 because 6(x-1) cancels out...?
or is it something completely different? 1 solutions
Answer 227137 by Fombitz(13828) on 2010-06-24 16:28:30 (Show Source):
You can put this solution on YOUR website!You're on the right track.
You can subtract fractions as long as you have the same denominator.
In this case you do.
You could also substitute to make it more visible.
If you let
 then the equation becomes,

However the denominator does go away or cancel out, it stays.
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Travel_Word_Problems/317150: When a car traveling on wet pavement at a speed V in miles per hour stops suddenly, it will produce skid marks of length S feet according to the formula
V=2(!3S)
If the length of the skid mark S (for a car that was in an accident)was 243 feet,
A) to find the speed V of a car.
B) If the speed limit on that road was 40 miles, by how many miles did the driver exceed the speed limit? 1 solutions
Answer 227120 by Fombitz(13828) on 2010-06-24 15:28:56 (Show Source):
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test/317260: Can intermediate value theorem be used to determine whether the function
f(x)=∣x∣−1 has a zero between x=−3 and x=3 ? Explain. 1 solutions
Answer 227116 by Fombitz(13828) on 2010-06-24 15:24:22 (Show Source):
You can put this solution on YOUR website!No.

.
.
All you can say is that on [-3,3] there is a value of  where  .
But you already know that because  .
So the intermediate value theorem can't help here.
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test/317256: Can intermediate value theorem be used to determine whether the function
f(x)=∣x∣−1 has a zero between
x=−3 and x=3 ? Explain. 1 solutions
Answer 227107 by Fombitz(13828) on 2010-06-24 15:15:22 (Show Source):
You can put this solution on YOUR website!No.

.
.
All you can say is that on [-3,3] there is a value of  where  .
But you already know that because  .
So the intermediate value theorem can't help here.
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test/317255: Using the intermediate value theorem determine, if possible, whether the function f(x)=2x^5−7x+1 has a real
zero between x=1 and x=2. 1 solutions
Answer 227101 by Fombitz(13828) on 2010-06-24 14:50:11 (Show Source):
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Probability-and-statistics/317225: The heights of all female college basketball players are normally distributed with a mean of 68 inches and a standard deviation of 2 inches. The probability that the height of a randomly selected female college basketball player is between 65.5 and 70.5 inches is? 1 solutions
Answer 227093 by Fombitz(13828) on 2010-06-24 13:54:47 (Show Source):
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Triangles/317235: the longest side of a triangle is 100 inches, the shortest side is 28 inches. How many incehs is the third side? 1 solutions
Answer 227091 by Fombitz(13828) on 2010-06-24 13:50:07 (Show Source):
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Probability-and-statistics/317201: The mean SAT score in mathematics is 485. The founders of a nationwide SAT preparation course claim that graduates of the course score higher, on average, than the national mean. Suppose that the founders of the course want to carry out a hypothesis test to see if their claim has merit. State the null hypothesis H_0and the alternative hypothesis H_1that they would use.
H_0=
H_1=
1 solutions
Answer 227090 by Fombitz(13828) on 2010-06-24 13:49:07 (Show Source):
You can put this solution on YOUR website!The null hypothesis would be H0:  . Their training increases test scores beyond the mean SAT score.
.
.
.
The alternative hypothesis would be H1:  .
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Numbers_Word_Problems/317155: Write the simplest form the ratio of the shaded area of the figure to the total area of the figure. This is a box with a triangle in the middle. The length of the box is x+8...the width of the box is x+4. The shaded triangle inside has a length of x+4....the width is 2x. Once again the back of the box says that the answer is x
----
x+8 but I am not sure how they got there. The most important part!!
1 solutions
Answer 227089 by Fombitz(13828) on 2010-06-24 13:43:39 (Show Source):
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test/317215: Find the zeros of the polynomial function f(x)=x^7−x^5−16x^3+16x and state the multiplicity of each.
1 solutions
Answer 227087 by Fombitz(13828) on 2010-06-24 13:35:02 (Show Source):
You can put this solution on YOUR website!
As you see from the graph, there are 5 real roots.
x=-2,-1,0,1,2
Each root has multiplicity of 1.
.
.
.
The polynomial found by these zeros is,

Divide the original polynomial by this polynomial to find the quadratic remainder.
.
.
.
First factor:

Subtract this from the original polynomial to get the remainder,

.
.
.
Next factor:

Subtract this from the remainder

.
.
.
So the remainder quadratic is  which has complex roots (  ,  )
.
.
.
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Radicals/317157: Simplify: sqrt (21) (sqrt(7) + sqrt(3))
a) 7 sqrt (3) + 3 sqrt(7)
b) 7 sqrt(3) + sqrt (3)
c) sqrt (210)
d) sqrt (147) + sqrt (63) 1 solutions
Answer 227072 by Fombitz(13828) on 2010-06-24 11:34:39 (Show Source):
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