Target Mathematics

1.1: Estimate roots using a graph

4PM1/1/November/2025 — Question 8 · 12 marks

1.1 diagram 1
(a) Complete the table of values for y=3x2y = 3^x - 2 giving your answers to one decimal place.
xx-1-0.500.250.50.7511.52
yy-1.7-113.27
(2)
(b) On the grid opposite, draw the graph of y=3x2y = 3^x - 2 for 1x2-1 \leq x \leq 2
(2)
(c) Use your graph to obtain an estimate, to one decimal place, of the value of log34.5\mathrm{log}_3 4.5
Show clearly how you have used your graph.
(3)
(d) By drawing a straight line on your grid obtain an estimate, to one decimal place, of the root of the equation log3(83x)x=0\mathrm{log}_3(8-3x) - x = 0 in the interval 1x2-1 \leq x \leq 2
(5)
Only use this grid if you need to redraw your graph.