1) (x+2) * x/3x+6

2) (-a^3/2b) ^2

3) y^2-4/3y * 2y^2/y^2-2y

4) 4ab/cx+dx * ax+bx/2ab

1) (x + 2) · x/3x + 6 = x (x + 2) / 3x = (x² + 2x) / 3x + 6 · 3x/3x = (x² + 2x) / 3x + 18x/3x =

= (x² + 2x + 18x) / 3x = (x² + 20x) / 3x = x (x + 20) / 3x = (x + 20) / 3

2) (-a³/2b) ² = (-a³) ² / (2b) ² = (-a^3 · 2) / 4b² = (-a⁶) / 4b²

3) (y² - 4) / 3y · 2y² / (y² - 2y) = (y² - 4) 2y²/3y (y² - 2y) = (y - 2) (y + 2) 2y²/3y · y (y - 2) =

= (y - 2) (y + 2) 2y²/3y² (y - 2) = 2 (y + 2) / 3 = (2y + 4) / 3

4) 4ab / (cx + dx) · (ax + bx) / 2ab = 4ab/x (c + d) · x (a + b) / 2ab = 4abx (a + b) / 2abx ·

· (c + d) = 2 (a + b) / (c + d) = (2a + 2b) / (c + d)