La a stim ca perioada din 6 e 6/9 , deci 25 x² = 6/9*3 =>x² = 2/25 => x = √2/5
La b √3x² = √75 => x² = √25 => x = √5
La c √2x²= 2√2 => x² = 2 => x = √2
La d √5x² = √245 => x² = √45 => x = √(3√5)
La e 16x² = 21 => x = √(21/16) = √21 / 4
La f 25x² = √729 => x = √(3³)/5 = 3√3/5
