P4.5.2 - Formation of simple differential

Formation of simple differential Questions involving connected rates of change may be set. equations.

Use formation of simple differential to connect the rule to the data and decision in the question.

This matters because formation of simple differential determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply formation of simple differential to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: Formation of simple differential is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.