3.6.5 Differentiation (A-level only)

A biological culture's sensitivity to a stimulant, $S$ , is modeled as a function of the concentration $c$ (in mmol/L) by the formula:

\left( \frac{1}{2}c^4 - \frac{8}{c} \right)^9

Use the chain rule to find an expression for the rate of change of sensitivity with respect to concentration, $dSdc\frac{dS}{dc}$ .

[3]

3.6.5 Differentiation (A-level only) Questions

A biological culture's sensitivity to a stimulant, $S$ , is modeled as a function of the concentration $c$ (in mmol/L) by the formula:

\left( \frac{1}{2}c^4 - \frac{8}{c} \right)^9

Use the chain rule to find an expression for the rate of change of sensitivity with respect to concentration, $dSdc\frac{dS}{dc}$ .

[3]