| Exam Board | CAIE |
| Module | FP1 (Further Pure Mathematics 1) |
| Year | 2013 |
| Session | June |
| Topic | Second order differential equations |
9 Find \(x\) in terms of \(t\) given that
$$4 \frac { \mathrm {~d} ^ { 2 } x } { \mathrm {~d} t ^ { 2 } } + 4 \frac { \mathrm {~d} x } { \mathrm {~d} t } + x = 6 \mathrm { e } ^ { - 2 t }$$
and that, when \(t = 0 , x = \frac { 5 } { 3 }\) and \(\frac { \mathrm { d } x } { \mathrm {~d} t } = \frac { 7 } { 6 }\).
State \(\lim _ { t \rightarrow \infty } x\).