UK-centric question: so I failed AS Level Maths back in 2014 and forgot pretty much everything I learnt. I'm currently using Khan Academy and LibGen to refresh my knowledge and I'm looking to take a part-time qualification later down the line.

Should I
>retake the A Level
or
>take a Level 3 BTEC in Core Maths(much easier than A Level Maths but it's free)