OCR MEI FP1 2014 June — Question 4

Exam BoardOCR MEI
ModuleFP1 (Further Pure Mathematics 1)
Year2014
SessionJune
TopicSequences and series, recurrence and convergence

4 Use the identity \(\frac { 1 } { 2 r + 3 } - \frac { 1 } { 2 r + 5 } \equiv \frac { 2 } { ( 2 r + 3 ) ( 2 r + 5 ) }\) and the method of differences to find \(\sum _ { r = 1 } ^ { n } \frac { 1 } { ( 2 r + 3 ) ( 2 r + 5 ) }\), expressing your answer as a single fraction.