IB Math AA HL 2021 May TZ1 paper 1 full solution (Section B)

[@hitzcritz]

Wow, the grade boundary for a 7 was a 63%?

[@kiddmath]

It was low but maybe not that low?

[@oliversp7428]

At 18:08, why is it (aˆ2+2a+1) and not (aˆ2+4a+4)? In the previous step we had (a+2)ˆ2 and not (a+1)ˆ2. Am I missing something?

[@kiddmath]

I factored out the 2, but u can also just expand

[@oliversp7428]

@@kiddmath oh alright, thanks