3 non-answers here! Thankfully, the asker can tell which is an answer and which are not...

To clarify, Bernard's answer is also not an answer because clearly the asker is at the high-school level and one should not talk about "differentials". Moreover, his notation "2dD(d)" is so sloppy that likely you know what he is talking about only if you already knew it before.

[ SmokeDetector | MS ] Bad keyword in answer, blacklisted website in answer, pattern-matching website in answer, potentially bad ip for hostname in answer, potentially bad keyword in answer, +1 more (261): (South Africa 2014) Finding angles in an obtuse triangle by patrickiong on math.SE

Need one more vote to delete: math.stackexchange.com/questions/3547732/…

Also, one more close vote here to allow for deletion.

please consider this PSQ for closure, as well.

Consider closure

Consider closure 2

consider closure 3

Delete: DA, DB, DC, DD, DE, DF, DG, DH

@RRL Two are now gone, the others need one more delete vote.

D1, D2, D3.

D4, D5, D6.

D7, D8, D9.

D10, D11, D12.

D13, D14, D15.

If you have any delete votes to spare, @user21820, see math.stackexchange.com/questions/3554004/…

@user21820 I'll pick up from D9 "tomorrow".

@amWhy: Thanks and your last posting is gone now.

@RRL Thanks!

close request

Delete: DI, DJ, DK, DL, DM, DN, DO, DP

@RRL I'm out of delete votes for now, but I will try to attend to those suggestions when my delete votes are replenished.