Его отличительная черта – нормированность, т. е. наличие правил (вы их учите в школе из года в год), соблюдение которых обязательно для всех членов общества.
what is the use of которых here? if i translate is, it would be: observation that is obligatory for all members of community?
if that's the case, why isn't it которые instead?
help!!
It is a tricky sentence. If который immediately follows a noun, it does not neccessarily refer to this noun. In rare cases, it may refer to any previous noun in the sentence. You encountered such a case.
If который refers to the immediately preceding noun, it is separated by comma, and matches the noun in number, case, and (if relevant) gender.
It который refers to another noun, there is no comma. It matches the noun by number, but the case is governed by the immediately preceding noun. Yes, it is that complicated.
In this sentence, которых must refer to правил. One reason is they are both in plural. Other nouns before которых are in singular. Besides, if it referred to any other noun, the sentence would be ill-formed, and make no sense. Finally, соблюдение правил is just a common phrase.
If который referred to соблюдение, this part of the sentence would be соблюдение, которое обязательно для всех членов общества (note the comma).
In your case, которых is in plural because правил is in plural. Которых is in genitive because соблюдение governs genitive.
"Который" is a pronoun which means it stands for, refers to, substitutes another noun. That another noun is called atecedent:
Ava arrived late because traffic held her up.
The pronoun her refers to and takes its meaning from Ava, so Ava is the antecedent of her.
Being able to find the antecedents of pronouns is very important, especially in long complex sentences with subordinate (dependent) clauses, like the one in your question.
In Russian where coordinative pronouns like "который" decline in cases, numbers, and genders, it's rather easy to find the antecedents. In your sentence, "которых" is plural and the only plural noun in that sentence is "правил" ("of the rules") which is the antecedent of "которых", that's the noun "которых" refers to.
if that's the case, why isn't it которые instead?
You can use "которые" like this
..., соблюдать которые обязательно для всех членов общества.
or
..., которые обязательны к соблюдению для всех членов общества.
