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

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The limit as x approaches 2 from the right for the expression (x+3) * |x+2| / (x+2) simplifies directly to 5. Since x is approaching 2, which is greater than -2, |x+2| equals x+2, allowing for straightforward cancellation. The discussion clarifies that absolute value considerations are only necessary when approaching -2, where the limit behavior differs based on the direction of approach.

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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.
 

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