# Math Help - need help plz sided limits

1. ## need help plz sided limits

plz need help
1>For function f(x) whose graph is given above state lim x->3+ f(x)
2>For function f(x) whose graph is given above state lim x->3- f(x)
3>For function f(x) whose graph is given above state lim x->3 f(x)
4>For function f(x) whose graph is given above state lim x->-2 f(x)

2. Originally Posted by gracy
plz need help
1>For function f(x) whose graph is given above state lim x->3+ f(x)
-2
2>For function f(x) whose graph is given above state lim x->3- f(x)
2
3>For function f(x) whose graph is given above state lim x->3 f(x)
Does not exists. Left and right limits are not the same.
4>For function f(x) whose graph is given above state lim x->-2 f(x)
-1

3. I can barely read your questions 9-12;

9.) I'm assuming it is lim(f(x), x, -3+) = 0 (therefore, d).

10.) lim(f(x), x, -3-) = 0 (therefore, d).

11.) lim(f(x), x, -3) = 0, since left and right limits are equal to 0, too. Thus, d again.

12.) lim(f(x), x, -2) = -1, (c), since the left and right limits are equal to -1, too. Note that f(-2), though, is -3.

Note: Try see the bigger picture. In this case, limits help us determine whether a graph is continuous, and therefore differentiable. The function f(x) is discontinuous when either the limit of f(x) does not exist and x approaches some arbitrary x or the limit exists, though does not equal f(a), as with #12.