Higher November 2021 Paper 3 Q22
22 Show that \(\dfrac{6x^3}{(9x^2 - 144)} \div \dfrac{2x^4}{3(x - 4)}\) can be written in the form \(\dfrac{1}{x(x + r)}\) where \(r\) is an integer. (3)
| Answer | Mark | Mark scheme |
|---|---|---|
| \(\dfrac{1}{x(x + 4)}\) | M1 | inverting the fraction and multiplying eg \(\dfrac{6x^3}{(9x^2 - 144)} \times \dfrac{3(x - 4)}{2x^4}\) |
| M1 | for factorising \(9x^2 - 144\), eg \((3x - 12)(3x + 12)\) | |
| A1 | cao |