WJEC Unit 3 2019 June — Question 1

Exam BoardWJEC
ModuleUnit 3 (Unit 3)
Year2019
SessionJune
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicPartial Fractions
TypeRepeated linear factor with distinct linear factor – decompose and integrate
DifficultyModerate -0.3 This is a standard partial fractions question with a repeated linear factor, requiring routine application of the cover-up method and standard integration of partial fractions. The decomposition is straightforward (form A/(x-1) + B/(x+2) + C/(x+2)²), and the integration involves only logarithms and a power rule, making it slightly easier than average but still requiring competent technique.
Spec1.02y Partial fractions: decompose rational functions1.08j Integration using partial fractions

a) Express \(\frac { 9 } { ( x - 1 ) ( x + 2 ) ^ { 2 } }\) in terms of partial fractions. b) Find \(\int \frac { 9 } { ( x - 1 ) ( x + 2 ) ^ { 2 } } \mathrm {~d} x\).

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a) Express $\frac { 9 } { ( x - 1 ) ( x + 2 ) ^ { 2 } }$ in terms of partial fractions.

b) Find $\int \frac { 9 } { ( x - 1 ) ( x + 2 ) ^ { 2 } } \mathrm {~d} x$.

\hfill \mbox{\textit{WJEC Unit 3 2019 Q1}}