[ 3 / biz / cgl / ck / diy / fa / ic / jp / lit / sci / vr / vt ] [ index / top / reports ] [ become a patron ] [ status ]
2023-11: Warosu is now out of extended maintenance.

/sci/ - Science & Math

View post   
File: 77 KB, 850x498, hand_study_II_by_GunnerRomantic.jpg [View same] [iqdb] [saucenao] [google]
5191437 No.5191437 [Reply] [Original]

Since Uni has started again, I decided to brush up my proof skills since I've neglected them before.

I was wondering about something simple, such as proving divisibility:

e.g. <span class="math"> 3 | 2^(2k +1) - 2 [/spoiler]

(inb4 homework thread: This is an example problem, I don't care about the solution, but instead about the approach with which you tackle it).

Is it just induction? I tried and didn't find a proper way to use it.

>> No.5191441

>>5191437
Forever failing Latex.

<span class="math"> 3 | 2^{2k + 1} -2 [/spoiler]

Is the correct example.

>> No.5191442

3|(4k+2-2)
3|4k

This is certainly not true.

>> No.5191444

>>5191441
Then yes, use induction.

>> No.5191459

bump

>> No.5191465

>>5191444
I'd fancy a hint, is there any property I can use to my advantage (if it doesn't give the solution away, since I want to solve it myself).

>> No.5191475

just go (mod 3)