A question prompted by the functions discussion: Are we *consistent* in the level of formality used at Alevel? This is not about whether we treat concepts in enough depth or with sufficient rigour, but rather whether once that level is set then we work with dependent topics at a similar level.

An example could be limits. We don't do them formally at all, and yet we pretend that we are doing differentiation properly ("from first principles") when all we really do is a bit of algebra and then "by the magic of limits" the answer drops out. #ALevelMaths#ITeachMaths#UKMathsChat

No (the fact that proof is labelled as it's own topic). When doing a 'proof' question, I think it's fair to say teachers pay close attention to the direction of implication but much of the time it's ignored. Many questions at A Level just require the right calculations appearing somewhere!