Step-by-step explanation:
If X is a finite Hausdorff space then every two points of X can be separated by open neighborhoods. Say the points of X are
. So there are disjoint open neighborhoods
and
, of
and
respectively (that's the definition of Hausdorff space). There are also open disjoint neighborhoods
and
of
and
respectively, and disjoint open neighborhoods
and
of
and
, and so on, all the way to disjoint open neighborhoods
, and
of
and
respectively. So
has every element of
in it, except for
. Since
is union of open sets, it is open, and so
, which is the singleton
, is closed. Therefore every singleton is closed.
Now, remember finite union of closed sets is closed, so
is closed, and so its complemented, which is
is open. Therefore every singleton is also open.
That means any two points of
belong to different connected components (since we can express X as the union of the open sets
, so that
is in a different connected component than
, and same could be done with any
), and so each point is in its own connected component. And so the space is totally disconnected.
The mean absolute deviation of the following set of data is 4.5
Step-by-step explanation:
We need to find the mean absolute deviation of the following set of data.
10,20,12,4,18,8,14,18
For finding mean absolute deviation, first we need to find the mean of the given data set.
The formula used to calculate mean is:
Sum of all data points: 10+20+12+4+18+8+14+18 = 104
Number of data points = 8
So, mean is:
Now, we will subtract 13 from the given data points:
10 - 13 = -3
20 - 13 = 7
12 - 13 = -1
4 - 13 = -9
18 -13 = 5
8 - 13 = -5
14 - 13 = 1
18 - 13 = 5
We will take absolute values i.e |-a|=a
So, now the numbers will be:
3,7,1,9,5,5,1,5
We will now find absolute mean deviation by finding mean of newly calculate values
Sum of all data points = 3+7+1+9+5+5+1+5
Number of data points = 8
So, the mean absolute deviation of the following set of data is 4.5
36 and 100 are both perfect squares
the factorization of x^2-y^2 is (x+y)(x-y)
substitute x^2 with 36x^2 and y^2 with 100y^2:
<span>36x^2-100y^2=
(6x+10y)(6x-10y) or
4(3x+5y)(3x-5y)</span>
Answer:
x=6+4
x<10
(-∞,10)
Step-by-step explanation:
Inequalities are the greater than, greater than or equal to, less than, or less than or equal to—between two numbers or algebraic expressions.