SGK Toán 8 tập 1 Chương I trang 16 tài trợ cho câu hỏi này nhé+))
\(\left(a+b\right)^2=a^2+2ab+b^2\)
\(\left(a-b\right)^2=a^2-2ab+b^2\)
\(a^2-b^2=\left(a-b\right)\left(a+b\right)\)
\(\left(a+b\right)^3=a^3+3a^2b+3ab^2+b^3\)
\(\left(a-b\right)^3=a^3-3a^2b+3ab^2-b^3\)
\(a^3+b^3=\left(a+b\right)\left(a^2-ab+b^2\right)\)
\(a^3-b^3=\left(a-b\right)\left(a^2+ab+b^2\right)\)
1, (A+B)2=A2+2AB+B2
2, (A-B)2=A2-2AB+B2
3, A2-B2=(A+B)(A-B)
4, (A+B)3=A3+3A2B+3AB2+B3
5, (A-B)3=A3-3A2B+3AB2-B3
6, A3+B3=(A+B)(A2-AB+B2)
7, A3-B3=(A-B)(A2+AB+B2)
