What do white circles on graphs mean - asymptotes/no values SAT MATH 2

Test Preparation
1

Title pls

2

Do you mean holes? http://www.purplemath.com/modules/grphrtnl4.htm

3

great thanks

4

They’re called discontinuities. If the limit at that point on the graph exists, it’s a removable discontinuity. If the limit does not exist, it’s a nonremovable discontinuity.