Edexcel FP2 — Question 12

Exam BoardEdexcel
ModuleFP2 (Further Pure Mathematics 2)
TopicPartial Fractions
TypeTwo linear factors in denominator

12. (a) Express \(\frac { 2 } { ( r + 1 ) ( r + 3 ) }\) in partial fractions.
(b) Hence prove that \(\sum _ { r = 1 } ^ { n } \frac { 2 } { ( r + 1 ) ( r + 3 ) } \equiv \frac { n ( 5 n + 13 ) } { 6 ( n + 2 ) ( n + 3 ) }\).