Usuń niewymiernosc z mianownika a) 4/pierwiastek z 2 -1 =

4/√2-1*√2+1 nad √2+1 = 4√2-4 nad 2-1 = 4√2-4=4(√2-1)

4 ----- = √2-1 4√2+4 -------= 2-1 4√2+4

4/√2-1=4(√2-1) / ( √2-1)( √2+1) = 4√2-4 / 1=4√2-4