A telecommunications engineer is modeling the signal strength, SSS microvolts, of a transmitter at a distance xxx km. A plot of log10S\log_{10} Slog10S against xxx produces a straight line lll.
The line lll passes through the points (0,3.42)(0, 3.42)(0,3.42) and (12,1.02)(12, 1.02)(12,1.02).
Write down an equation for lll.
Hence, or otherwise, express SSS in the form kbxkb^xkbx, giving the values of the constants kkk and bbb to 3 significant figures.
202 exam-style questions on Edexcel A Level Maths Regression, Correlation and Hypothesis Testing, covering 1.1 Exponential Models, 1.2 Measuring Correlation, and 1.3 Hypothesis Testing for Zero Correlation. Each one has a worked solution and a mark scheme showing where the marks go.