Target Mathematics

1.54: Logarithmic equations, exponential equations and graphical solution

4PM1/2/January/2016 — Question 11 · 11 marks

1.54 diagram 1
(a) Complete the table of values for y=ex1+2y=e^{x-1}+2. Give your answers to 2 decimal places where appropriate.
xx-2-10123
f(x)f(x)2.054.729.39
(2)
(b) On the grid opposite, draw the graph of y=ex1+2y=e^{x-1}+2 for 2x3-2\le x\le3. (2)
(c) Use your graph to obtain an estimate, to 1 decimal place, of the root of the equation 4=ex14=e^{x-1} in the interval 2x3-2\le x\le3. (2)
(d) By drawing a straight line on the grid, obtain an estimate, to 1 decimal place, of the root of the equation ln(4x4)=x1\ln(4x-4)=x-1 in the interval 2x3-2\le x\le3. (5)