Упростите: 1) (2b-1)(1+2b+4b^2)2) (a+b)(a^2+b^2)-(a^3+b^3)3)...

Question

Упростите:
1) (2b-1)(1+2b+4b^2)
2) (a+b)(a^2+b^2)-(a^3+b^3)
3) (7c^2+2)(-49c^4+14c^2-4)
Заранее спасибо :)))

Answer 1

1) 2b+4b^2+8b^3-1-2b-4b^2=8b^3-1
2)a^3+ab^2+a^2b+b^3-a^3-b^3=ab^2+a^2b=ab(b+a)
3)-343c^8+98c^4-28c^2-98c^4+28c^2-8=-343c^8-8

Answer 2

1) (2b)^3-1^3=8b^3-1
2) (a+b)(a^2+b^2)-(a+b)(a^2-ab+b^2)=(a+b)(a^2+b^2-a^2+ab-b^2)=(a+b)*ab
3) -(7c^2+2)(49c^4-14c^2+4)=-((7c^2)^3+2^3)=343c^6+8