The output power level PPP of a specific amplifier, in decibels, depends on the signal strength sss according to the function:
P(s)=5+2lns,s>0 P(s) = 5 + 2\ln s, \quad s > 0 P(s)=5+2lns,s>0The signal strength SSS produced by a sensor over time ttt (in seconds) is given by:
S(t)=12t−182t+3,t>1.5 S(t) = \frac{12t - 18}{2t + 3}, \quad t > 1.5 S(t)=2t+312t−18,t>1.5Determine the value of P−1(9)P^{-1}(9)P−1(9).
Use differentiation to show that SSS is an increasing function for all t>1.5t > 1.5t>1.5.
Find an expression for the inverse function S−1(x)S^{-1}(x)S−1(x).
Determine the range of the composite function PSPSPS.
471 exam-style questions on Edexcel A Level Maths Functions and Graphs, covering 2.1 The Modulus Function, 2.2 Functions and Mappings, 2.3 Composite Functions, 2.4 Inverse Functions, 2.5 y=|f(x)| and y=f(|x|), 2.6 Combining Transformations, and 2.7 Solving Modulus Problems. Each one has a worked solution and a mark scheme showing where the marks go.