Question

[Bối Bối]

Cho \(P=\frac{a^3-a-2b-\frac{b^2}{a}}{\left(1-\sqrt{\frac{1}{a}+\frac{b}{a^2}}\right)\left(a+\sqrt{a+b}\right)}:\left(\frac{a^3+a^2+ab+a^2b}{a^2-b^2}+\frac{b}{a-b}\right)\)

a) CMR: \(P=a-b\)

b) Tìm a, b biết P=1 và \(a^3-b^3=7\)