Cho \(\left\{{}\begin{matrix}a+b+c=2\\a^2+b^2+c^2=2\end{matrix}\right.\)

Tính \(P=\sqrt{\left(a+1\right)\left(b+1\right)\left(c+1\right)}.\left(\dfrac{a}{1+a^2}+\dfrac{b}{1+b^2}+\dfrac{c}{1+c^2}\right)\)

phân tích đa thức thành nhân tử

1.\(\left(a^2+b^2+ab\right)^2-a^2b^2-b^2c^2-c^2a^2\)

2.\(a^4+b^4+c^4-2a^2b^2-2b^2c^2-2a^2c^2\)

3.\(a\left(b^3-c^3\right)+b\left(c^3-a^3\right)+c\left(a^3-b^3\right)\)

4.\(a^6-a^4+2a^3+2a^2\)

5.\(\left(a+b\right)^3-\left(a-b\right)^3\)

6.\(x^3-3x^2+3x-1-y^3\)

7.\(x^{m+4}+x^{m+3}-x-1\)