/sci/ - Science & Math

>>14878740
Tyvm anon

>>14631106
oh wow nevermind i got it just now.

the first sum also has a (n-1) that doesnt cancel out either so its:
2Sn = ((n-1) +n) + ((n-1)*(n) -1)
and then
2Sn = n^2 +n -2
Sn = (n^2+n)/2 - 1

>>14610441
>It's more confusion with indices
I think it must be a big part of it, ty, i will try again tomorrow also the website you linked is very cool

ty again anon i appreciate all your help very much

>>14559833
ty anon that's really cool i appreciate your explanation

>>14489094
i think i can help with that anon.
1. before starting the exam, quickly flip through and see how many questions there are, which are multi-part, which want long writing sequences, proofs etc, and estimate how much time you have for each question.
2. read over each question, gauge how easy it will be to solve, or if you can solve it or not. if you aren't sure, mark it with an asterisk and go to the next question, and do the same.
3. after the last question you now have an idea of which questions you can easily solve and which you cant.
4. do the questions you can quickly solve first, then the ones that look a little more time consuming, then the ones you are unsure of for last. while doing this always be making sure that if you hit your self-imposed time limit on the x minutes/question, you will leave it there and move to the next.
5. once you have the easy questions done and the longer ones, finish any that you ran out of time to do before and had to move on.
6. then attempt to solve the ones you marked with an asterisk, but make sure to give time to try and solve each one, so dont go to your first asterisk question and sit there pondering for 20 minutes on that one question. move between them and try to solve as much as you can from each of them.

as for finishing exams faster, you should try printing out a series of easy, medium, and hard questions from the book, arrange them into an exam format, then try to solve them while sticking to the alotted time. use the same principles above for prioritizing questions.

then just try and be mindful of yourself while doing it. try and notice where you are spending a lot of time, and how you might be able to improve it. eg instead of reading the question over and over, write everything you know and is given, and all the relevant ways to manipulate that data that could get you your result.

try and make a habit of checking the time at least every 5 minutes, and force yourself to move on to the next question