Verified answer

a) 5a(2a² + 4a - 3) = 10a³ + 20a² - 15a

б) 4a²(5 - 6a + 3a²) = 20a² - 24a³ + 12a⁴ = 12a⁴ - 24a³ + 20a²

в) 0,8x(7 - 8x + 9x²) = 5,6x - 6,4x² + 7,2x³ = 7,2x³ - 6,4x² + 5,6x

г) - 2,5x(4x² - 6,4x + 7) = - 10x³ + 16x² - 17,5x

д) 6x(4 - 5x) + 3(10x² - 6x) - 6(x - 3) = 24x - 30x² + 30x² - 18x - 6x + 18 =

=18

е) x - 2(x - 3(x + 4) + 5 = x - 2(x - 3x - 12) + 5 = x - 2(- 2x - 12) + 5 =

= x + 4x + 24 + 5 = 5x + 29