-3 -3*(1+√7) -3*(1+√7) -3*(1+√7) 1+√7
------------- = ----------------------- = --------------------- = ------------------------ = ------------------
1-√7 (1-√7)(1+√7) 1 ² - √7² -6 2
19 19*(2√5 +1) 19*(2√5 +1) 19*(2√5 +1)
---------------- = ----------------------------- = ------------------------- = --------------------- = 2√5 +1
2√5 - 1 (2√5 -1)(2√5 +1) (2√5)²-1² 20-1
1-√2 (1-√2)(1-√2) (1-√2)²
-------------- = ------------------------ = -------------------- = - (1-√2)²
1+√2 (1+√2)(1-√2) 1²- √2²