2.1)a²¹·a¹³/a³¹=a²¹⁺¹³⁻³¹=a³;
a=1.6⇒a³=4.096;
a=-0.11⇒a³=-0.001331.
2)n⁴⁸/n¹⁹n²⁶=n⁴⁸⁻¹⁹⁻²⁶=n³;
n=0.3;⇒n³=0.027;
n=-0.4;⇒n³=-0.064.
3,1)(-2/3·a²b⁶c)³·9a⁵bc²=(-2/3)³·9·a⁶⁺⁵·b¹⁸⁺¹·c³⁺²=
=-8·9/27·a¹¹·b¹⁹·c⁵=-8/3·a¹¹·b¹⁹·c⁵=-2²/₃·a¹¹·b¹⁹·c⁵;
2)12·x²·y·z⁷·(0.5x³y⁸)²=12·0.25·x²⁺⁶·y¹⁺¹⁶·z⁷=3·x⁸·y¹⁷·z⁷;
3)(36m⁸n²k):(12m²n)=36/12·m⁸⁻²·n²⁻¹·k=3·m²nk;
4)(-5/9·a⁹·b⁸·c⁷):(5·a³·b³·c)=-5/(9·5)·a⁹⁻³·b⁸⁻³·c⁷⁻¹=-1/9·a⁶·b⁵·c⁶;
4,1)5a³b-3ab²+4ab²-7a³b=a³b(5-7)+ab²(-3+4)=
=-2a³b+ab²=ab(-2a²+b);
2)2xy²z³-3xyxy+8x²y²z²-14=2xy²z³-3x²y²+8x²y²z²-14;
3)1¹/₃ab·(-6a²b)-0.7a³·20b-b²·7a³=-4·6/3·a¹⁺²b¹⁺¹-0.7·20a³b-7a³b²=
=-8a³b²-14a³b-7a³b²=-15a³b²-14a³b;