a: \(B=\dfrac{a+1-2\sqrt{a}}{a+1}:\dfrac{a+1-2\sqrt{a}}{\left(\sqrt{a}+1\right)\left(a+1\right)}=a+1\)
Khi a=2023-2căn 2022 thì
B=2023-2căn 2022+1=2024-2căn 2022
b: \(A^3=1+\sqrt{\dfrac{56}{54}}+1-\sqrt{\dfrac{56}{54}}+3\cdot A\cdot\sqrt[3]{1-\dfrac{56}{54}}\)
\(\Leftrightarrow A^3=2+3\cdot A\cdot\dfrac{-1}{3}\)
=>A^3-2+A=0
=>A=1