The first term of an arithmetic progression is ,a , and the common difference is -4.the first term of a geometric progression is ,5a, and the common ratio is -1/4. The sum to infinity of the geometric progression is equal to the sum of the first eight terms of the arithmetic progression. Find the value of ,a,.
AAAaannndd the bot gets it wrong yet again!
a/(1-r) = 8/2 (2a+7d)
so
5a/(1 + 1/4) = 4(2a-28)
a = 28