27 = 3³
12 = 2² · 3
8 = 2³
daca impartim cu 12 ; avem 27 /12 = 9 /4 = ( 3 /2)²
8 / 12 = 2 / 3
daca notam ( 3 / 2)^x = y
ecuatia y² + 1 = 2 / y
y³ + y = 2
y³ + y - 2 = 0
( y³ - 1) + ( y -1) = 0
( y -1) ) ·(y² + y + 1 ) + ( y -1) = 0
( y -1) ·( y² + y + 1 +1) = 0
solutia y = 1 atunci 3 /2^x = 1 = ( 3 /2) °
atunci x = 0
ec. y² + y +2 = 0 , cu Δ=1 - 8 = - 7 nu are solutii in R
