- I’m assuming the expression implies the following:
(1-n)/(n^2 - 1)
The steps goes as follows:
= -(n-1)/(n^2-1) (factored a negative out)
= -(n-1)/[(n+1)(n-1)] (Factored denominator into a difference of squares, but don’t just blindly accept the fact, expand it and you should get the original denominator)
At this point, the (n-1) terms cancel, as you should know: a real number, besides 0, over itself is 1.
= -1/(n+1) , which is the answer
Note: You could also see it as 1/-(n+1) or 1/(-n-1)
Answer:
American Crows can be considered partially migratory. That is, some populations migrate, others are resident, and in others only some of the crows migrate. Crows in the southern parts of their range appear to be resident and not migrate. They may make some changes in their use of space at this time, spending more time off the territory to forage and roost. Crows migrate out of the northern most parts of their range. It has been stated that crows migrate out of those areas where the minimum January temperature averages 0 ° F. Certainly crows leave the northern Great Plains in the fall, leaving Saskatchewan and Alberta to winter in the lower Plains states of Nebraska, Kansas, and Oklahoma (Kalmbach, E. R., and S. E. Aldous. 1940. Winter banding of Oklahoma crows. Wilson Bull. 52: 198-206). Crows can be seen crossing the Great Lakes in spring and fall, and these birds undoubtedly are migrating to and from parts of Canada.
Step-by-step explanation:
because They may make some changes in their use of space at this time, spending more time off the territory to forage and roost. Crows migrate out of the northern most parts of their range. It has been stated that crows migrate out of those areas where the minimum January temperature averages 0 ° F.
Answer:
volume of cyclinder=πr²h
=3.14×2²×3=37.68cm³
rectangular prism volume=6×5×7
=210cm³
total volume=37.68+210=247.68cm³
2x + y = 5
x − 2y = 10
y = 5 − 2x
x − 2(5 − 2x) = 10
x − 10 + 4x = 10
5x − 10 = 10
<em>add 10 to each side</em>
<em>5x-10+10 = 10 + 10</em>
<em>5x=20</em>
5x = 0 <em>this is the error</em>
He needs to add 10 to each side
Answer:
Step-by-step explanation:
Let many universities and colleges have conducted supplemental instruction(SI) programs. In that a student facilitator he meets the students group regularly who are enrolled in the course to promote discussion of course material and enhance subject mastery.
Here the students in a large statistics group are classified into two groups:
1). Control group: This group will not participate in SI and
2). Treatment group: This group will participate in SI.
a)Suppose they are samples from an existing population, Then it would be the population of students who are taking the course in question and who had supplemental instruction. And this would be same as the sample. Here we can guess that this is a conceptual population - The students who might take the class and get SI.
b)Some students might be more motivated, and they might spend the extra time in the SI sessions and do better. Here they have done better anyway because of their motivation. There is other possibility that some students have weak background and know it and take the exam, But still do not do as well as the others. Here we cannot separate out the effect of the SI from a lot of possibilities if you allow students to choose.
The random assignment guarantees ‘Unbiased’ results - good students and bad are just as likely to get the SI or control.
c)There wouldn't be any basis for comparison otherwise.
