Moderate -0.8 This is a straightforward integration problem requiring substitution of u=4x+5, followed by applying a boundary condition to find the constant, then evaluating at x=5. The substitution is obvious, the integration is routine (power rule), and it's a standard single-method question worth modest marks. Easier than average A-level questions.
3 A curve is such that \(\frac { \mathrm { dy } } { \mathrm { dx } } = 3 ( 4 \mathrm { x } + 5 ) ^ { \frac { 1 } { 2 } }\). It is given that the points \(( 1,9 )\) and \(( 5 , a )\) lie on the curve. Find the value of \(a\).
3 A curve is such that $\frac { \mathrm { dy } } { \mathrm { dx } } = 3 ( 4 \mathrm { x } + 5 ) ^ { \frac { 1 } { 2 } }$. It is given that the points $( 1,9 )$ and $( 5 , a )$ lie on the curve. Find the value of $a$.\\
\hfill \mbox{\textit{CAIE P1 2024 Q3 [5]}}