SOLUTION: solve the following inequality[1/x-2> or =1] and graph the solution on the real number line

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Question 1162206: solve the following inequality[1/x-2> or =1] and graph the solution on the real number line
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
matrix%281%2C3%2C%0D%0A1%2F%28x-2%29%2C%22%22%3E=%22%22%2C1%29

Get 0 on the right:

matrix%281%2C3%2C%0D%0A1%2F%28x-2%29-1%2C%22%22%3E=%22%22%2C0%29

Get LCD

matrix%281%2C3%2C%0D%0A1%2F%28x-2%29-%28x-2%29%2F%28x-2%29%2C%22%22%3E=%22%22%2C0%29

matrix%281%2C3%2C%0D%0A%281-%28x-2%29%29%2F%28x-2%29%2C%22%22%3E=%22%22%2C0%29

matrix%281%2C3%2C%0D%0A%281-x%2B2%29%2F%28x-2%29%2C%22%22%3E=%22%22%2C0%29

matrix%281%2C3%2C%0D%0A%283-x%29%2F%28x-2%29%2C%22%22%3E=%22%22%2C0%29

The critical values are when the numerator or
the denominator equals 0:

The numerator is 0 when x = 3
The denominator is 0 when x = 2

So we draw a number line and mark the critical 
numbers

-----------------o---o- ---------
-2  -1   0   1   2   3   4   5  6

This divides the number line into three intervals

We pick a test value in the left-most interval.
The easiest number there to pick for a test value
is 0, so we substitute it in the inequality:

matrix%281%2C3%2C%0D%0A%283-x%29%2F%28x-2%29%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A%283-0%29%2F%280-2%29%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A-3%2F2%2C%22%22%3E=%22%22%2C0%29

That's false so we do not shade the numbers in the
left most region, so we still have

-----------------o---o-----------
-2  -1   0   1   2   3   4   5  6

We pick a test value in the middle interval, between
2 and 3. The easiest number there to pick for a test value
is 2.5, so we substitute it in the inequality:

matrix%281%2C3%2C%0D%0A%283-x%29%2F%28x-2%29%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A%283-2.5%29%2F%282.5-2%29%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A0.5%2F0.5%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A1%2C%22%22%3E=%22%22%2C0%29

That's true so we shade the numbers in the
middle region, so we now have

-----------------o===o---------- 
-2  -1   0   1   2   3   4   5  6


We pick a test value in the right-most interval, greater
than 3. The easiest number there to pick for a test value
is 4, so we substitute it in the inequality:

matrix%281%2C3%2C%0D%0A%283-x%29%2F%28x-2%29%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A%283-4%29%2F%284-2%29%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A-1%2F2%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A1%2C%22%22%3E=%22%22%2C0%29

That's false so we do not shade the numbers in the
right-most region, so we have

-----------------o===o----------- 
-2  -1   0   1   2   3   4   5  6

Finally we test the critical numbers themselves:

We test 2

matrix%281%2C3%2C%0D%0A%283-x%29%2F%28x-2%29%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A%283-2%29%2F%282-2%29%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A1%2F0%2C%22%22%3E=%22%22%2C1%29

1/0 is not defined, so we do not shade at 2

We test 3

matrix%281%2C3%2C%0D%0A%283-x%29%2F%28x-2%29%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A%283-3%29%2F%283-2%29%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A0%2F1%2C%22%22%3E=%22%22%2C0%29
matrix%281%2C3%2C%0D%0A0%2C%22%22%3E=%22%22%2C0%29

That's true so we do shade at 3

-----------------o===☻----------- 
-2  -1   0   1   2   3   4   5  6

Interval notation:

matrix%281%2C5%2C%0D%0A%0D%0A%22%28%22%2C2%2C%22%2C%22%2C3%2C%22%5D%22%29

Edwin