Решите уравнение

2) (х-3) (х2+3 х+9) - х (х2-16) = 21

4) 16 х (4 х2-5) + 17 = (4 х+1) (16 х2-4 х+1)

2) (х-3) (х2+3 х+9) - х (х2-16) = 21

x³-3³ - (x³-16x) = 21

x³-27-x³+16x=21

16x=21+27

16x=48

x=48:16

x=3

4) 16 х (4 х2-5) + 17 = (4 х+1) (16 х2-4 х+1)

16*4*x³-5*16x+17 = (4x) ³+1

64x³-80x+17=64x³+1

80x=64x³-64x³+17-1

80x=16

x=16:80

x=1/5=0.2