Periksalah pecahan. Kalikan pecahan dengan konjugasi penyebutnya. Sederhanakan sesuai kebutuhan.

I'm interested in that, but I only have a few mins. Can you give me at most the first 500 characters of a detailed explanation in English about that?
If your fraction contains a sum of two terms in the denominator, at least one of which is irrational, then you cannot multiply the fraction by it in the numerator and denominator. 42+2{\displaystyle {\frac {4}{2+{\sqrt {2}}}}} To see why this is the case, write an arbitrary fraction 1a+b,{\displaystyle {\frac {1}{a+b}},} where a{\displaystyle a} and b{\displaystyle b} are irrational. Then the expression (a+b)(a+b)=a2+2ab+b2{\displaystyle (a+b)(a+b)=a^{2}+2ab+b^{2}} contains a cross-term 2ab.{\di