Now look at the sample solution below: consider both mathematical accuracy and style.

Click on ‘Reveal answer’ to see the tutor's marking.
OpenLearn - Language, notation and formulas
Except for third party materials and otherwise, this content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence, full copyright detail can be found in the acknowledgements section. Please see full copyright statement for details.