June 2017 Paper 1 Q6
6 Factorise fully \(\qquad (x + 6)^4 + (x + 6)^3(3x + 4)\)
Do not attempt to expand the brackets. [3 marks]
| Answer | Mark | Comments |
|---|---|---|
| \((x + 6)^3\,[x + 6 + 3x + 4]\) or \((x + 6)^2[(x + 6)^2 + (x + 6)(3x + 4)]\) or \((x + 6)[(x + 6)^3 + (x + 6)^2(3x + 4)]\) | M1 | for sight of \((x + 6)^3\), \((x + 6)^2\) or \((x + 6)\) taken out as a common factor |
| \((x + 6)^3[4x + 10]\) | A1 | |
| \(2(x + 6)^3(2x + 5)\) | A1 |
Additional guidance
\((x + 6)^3(x + 6)(3x + 4)\) implies M1
SC1 for all correct factors seen in working but never written as a product of terms
An attempt to expand brackets will be M0 unless the expansion leads to a correct solution worth 2 or 3 marks
\((x + 6)^3\,[x + 6 + 4x + 3]\) scores M1 ... ignore the error in the 2nd bracket