qwuebek

1. (4х+0,1у)³=(4х)³+3×(4х)²×(0,1у)+3×(4х)×(0,1у)²+(0,1у)³=64х³+4,8х²у+0,12ху²+0,001у³

2. (0,2а+30б)³=(0,2а)³+3×(0,2а)²×30б+3×(0,2а)×(30б)²+(30б)³=0,008а³+3,6а²б+540аб²+27000б³