Find One Sided Limit: x-->2+ (x+3) * |x+2| / x+2

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In summary: Since these two limits are different, the limit does not exist.In summary, when taking the limit of (x+3)|x+2|/(x+2) as x approaches 2, there is no need to worry about "one sided" limits since x+2 will always be positive. The limit evaluates to 5. However, if the limit were being taken as x approaches -2, the limit would not exist due to the difference between the limit from below and the limit from above.
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ur5pointos2sl
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The question is: Find

lim x-->2+ (x+3) * |x+2| / x+2

I am confused about the absolute value problems. I cannot seem to grasp in my mind how to define this problem piecewised. Any help to get me started would be appreciated.
 
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ur5pointos2sl said:
The question is: Find

lim x-->2+ (x+3) * |x+2| / x+2

I am confused about the absolute value problems. I cannot seem to grasp in my mind how to define this problem piecewised. Any help to get me started would be appreciated.
Actually, there is no problem with the absolute value in this problem! |x| "breaks" when x= 0 so |x+2| "breaks" when x+ 2= 0 or x= -2. Since here you are taking the limit as x goes to 2, not -2, for x "close to 2" (larger than -2) x+2> 0 and this is exactly like
[tex]\lim_{x\rightarrow 2} (x+3)*(x+2)/(x+2)= \lim_{x\rightarrow 2} x+ 3= 2+ 3= 5[/tex].

Now, if the limit were being taken as x goes to -2, THEN you would need to worry about "one sided" limits. No matter how close x is to -2, it could still be either < -2 or > -2.
If x< -2, then x+ 2 is negative and so |x+2|= -(x+2). |x+2|/(x+2)= -(x+2)/(x+2)= -1 so
(x+3)|x+2|/(x+2)= -(x+3) and the limit, as x goes to -2 from below, is -(-2+3)= -1.

But if x> -2, then x+2>0 so |x+2|= x+2 and |x+2|/(x+2)= 1 so (x+3)|x+2|/(x+2)= x+ 3 and the limit, as x goes to -2 from above, is (-2+3)= 1.
 

1. What is a one-sided limit?

A one-sided limit is a way to determine the behavior of a function as it approaches a specific value from only one direction. In this case, we are looking at the behavior of the function as x approaches 2 from the positive side, denoted as x→2+.

2. How do you find a one-sided limit?

To find a one-sided limit, we evaluate the function at values that are approaching the specified value from the given direction. In this case, we would evaluate the function at values slightly larger than 2, such as 2.1, 2.01, 2.001, etc.

3. What is the difference between a one-sided limit and a two-sided limit?

A one-sided limit only considers the behavior of a function approaching a specific value from one direction, while a two-sided limit considers the behavior from both the positive and negative sides of the specified value.

4. How do you handle absolute value in a one-sided limit?

In a one-sided limit, absolute value is handled by only considering values on the specified side of the given value. In this case, we would only consider values larger than 2, as we are approaching from the positive side.

5. What is the one-sided limit of the given function at x=2?

The one-sided limit of the given function as x approaches 2 from the positive side is 5. This can be found by evaluating the function at values approaching 2 from the positive side, such as 2.1, 2.01, 2.001, etc. and observing that the values approach 5 as x gets closer to 2.

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