OCR C2 2006 January — Question 5

Exam BoardOCR
ModuleC2 (Core Mathematics 2)
Year2006
SessionJanuary
TopicGeometric Sequences and Series

5 In a geometric progression, the first term is 5 and the second term is 4.8 .
  1. Show that the sum to infinity is 125 .
  2. The sum of the first \(n\) terms is greater than 124 . Show that $$0.96 ^ { n } < 0.008$$ and use logarithms to calculate the smallest possible value of \(n\).