1) a^2 = 0,25, a = +-0,5, a^3 = +-0,125
2) a^2 = 400, a = +-20, <span> a^3 = 8 000</span>
1) a^3 = 0,008, a = 0,2, a^2 = 0,04
2) a^3 = 125, a = 5, <span> a^2 = 25.</span>
<span>(x+7)(x²-7x+49)=x(x+8)(x-7)</span>