Maths  Geometric Progression
posted by Anonymous .
The second term of a GP is 1/2 and the sum ti infinity of the series is 4. Find the first term and and the common ratio of the series.

Maths  Geometric Progression 
Steve
ar = 1/2
a/(1r) = 4
a = 2√2
r = 1/4 (2+√2)
or
a = 2+√2
r = 14 (2√2)
Respond to this Question
Similar Questions

math studies
An arithmetic series has a first term of 4 and a common difference of 1. A geometric series has a first term of 8 and a common ratio of 0.5. After how many terms does the sum of the arithmetic series exceed the sum of the geometric … 
GP Caluculus
The third term of a geometric progression is 16. The sum of the third term and the fourth term is 8.Find (a)the first term and the common ratio of the progression. (b)the sum of infinity of the progression. 
Geometric Series (Algebra 2)
I need some assistance or a formula when trying to find the first term of geometric series please! I don't understand this!!!! What is the first term of a geometric series with a summation of 289, 5 terms and a common ratio of 1/2? 
Maths
1..The first 2 terms of a geometric progression are the same as the first two terms of an arithmetic progression.The first term is 12 and is greater than the second term.The sum of the first 3 terms od the arithmetic progression is … 
Math(arithmetic & Geometric Series)
1)The sum of 6 terms of an arithmetic series is 45, the sum of 12 terms is 8. Find the first term and the common difference? 
maths and science
The first term of a geometric sequence is 125÷4,the last term is 2, and the sum of the associated series is 203÷4. What is the common ratio and how many terms are there in the series? 
math C2 sequences and series
The eight,fourth and second terms of an arithmetic progression form the first three terms of a geometric series. The arithmetic progression has first term A and common difference d, and the geometric progression has first term G and … 
plz sequence sir steve reiny bob damon i need u
The three real,distint and nonzero numbers a,b,c are such that a,b,c are in arithmetic progression and a,c,b are in geometric progression. Find the numerical value of the common ratio of the geometric progression.. Hence,find an expression … 
maths
The first term of a geometric sequence is 31(1/4),the last term is 2 and the sum of the associated series is 50(3/4).what is the common ratio and how many terms are there in the series? 
algebra, series
The sum of the first n terms of a series is 1(3/4). Obtain an expression for the nth term of the series. Prove that the series is geometric, and state the values of the first term and the common ratio. Please show workings