Question

2) (0,3b^3 + x)(0,3b^3 – x);
4) (21d^2 - k^3)(21d^2 +k^3);
6) (1,9c^4+ 6d)(6d-1,9c^4); ​
ДАЮ 50 БАЛЛОВ

Answer 1

(0,3b³)²-x² = 0.09b⁶-x²

(21d²)²-(k³)² = 441d⁴-k⁶

(1,9c^4+ 6d)(6d-1,9c^4) = (6d-1,9c^4)(6d+1,9c^4) = (6d)²-(1.9c⁴)² = 36d²-3.61c⁸