Each of the following represents an infinite geometric series. For what values of x will each series be convergent?
Problem 1 :
5 + 5x + 5x² + 5x³ + …
Problem 2 :
1 + x/3 + x²/9 + x³/27 + …
Problem 3 :
2 + 4x + 8x² + 16x³ + …
Problem 4 :
The infinite series given by
1 + 3x + 9x² + 27x³ + …
has a sum of 4. What is the value of x?
List the first four terms of the series.
Problem 5 :
Dominique and Rita are discussing the series
-1/3 + 4/9 - 16/27 + ...
Dominique says that the sum of the series is -1/7.
Rita says that the series is divergent and has no sum.
a. Who is correct?
b. Explain your reasoning.
1) The value of r = x is in the interval -1 < x < 1.
2) So, when -3 < x < 3, the series converges.
3) -1/2 < x < 1/2
4) x = 1/4,
The first four terms are
= 1 + 3/4 + 9/16 + 27/64 + …
5) a) Rita is correct, because the given series is divergent.
b) Since it is divergent, we can not figure out the sum.
May 21, 24 08:51 PM
May 21, 24 08:51 AM
May 20, 24 10:45 PM