### Home > CALC > Chapter 9 > Lesson 9.4.2 > Problem 9-129

9-129.

For an infinite geometric series:

For a finite geometric series:

Substitute *a* = 1/2 and *r* = 1/2 into the formulas in the hints then evaluate.

9-129.

For an infinite geometric series:

For a finite geometric series:

Substitute *a* = 1/2 and *r* = 1/2 into the formulas in the hints then evaluate.