Higher January 2019 Paper 2 Q17
17 f is the function such that \(\mathrm{f}(x) = 4 - 3x\)
(a) Work out \(\mathrm{f}(5)\) (1)
g is the function such that \(\mathrm{g}(x) = \dfrac{1}{1 - 2x}\)
(b) Find the value of \(x\) that cannot be included in any domain of g (1)
(c) Work out \(\mathrm{fg}(-1.5)\) (2)
| Scheme | Marks |
|---|---|
| \(-11\) | B1 |
| (1) |
| Scheme | Marks |
|---|---|
| 0.5 oe | B1 |
| (1) |
| Scheme | Marks |
|---|---|
\(\mathrm{g}(-1.5) = 1 \div (1 - 2 \times -1.5)\) (=0.25) or \(\mathrm{fg}(x) = 4 - 3 \times \left(\dfrac{1}{1 - 2x}\right)\) oe | M1 |
| 3.25 oe | A1 |
| (2) | |
| (4 marks) |
Notes
M1: \(\mathrm{g}(-1.5)\) must be the correct calculation alone.