\(A=\left(\dfrac{1}{\sqrt{a}}+\dfrac{1}{1-\sqrt{a}}\right).\dfrac{\sqrt{a}-a}{\sqrt{a}-2}\)

\(B=\left(\dfrac{\sqrt{x}}{2}-\dfrac{1}{2\sqrt{x}}\right).\dfrac{4x}{x-1}\)

rút gọn

rút gọn 

\(B=\dfrac{4}{\sqrt{x}+1}+\dfrac{2}{1-\sqrt{x}}-\dfrac{\sqrt{x}-5}{x-1}\)

\(M=\left(\dfrac{1}{\sqrt{x}-1}-\dfrac{1}{\sqrt{x}+1}\right):\dfrac{x+1}{x-1}\)

phân tích đa thức thành nhân tử

a)2(x-1)³-5x(x-1)²-(x-1)

b)13x⁴y³-26x²y²z²-39xy²z³

c)\(\dfrac{1}{2}x\left(x^2-4\right)+4\left(x+2\right)\)

d)\(x^4+5x^3-8x-40\)

e)\(8x\left(x-2017\right)-2x+4034\)

E =(x+2)³+(x-2)³+x³-3x(x+2)(x-2)

tại x = 3

F =(x+1)³-(x-1)(x²+x+1)-3(x+1)+2

tại x =2024

D = (3x+2)(9x²-6x+4)-3(9x³-2)

tại x = -2

C = 5(x+3)(x-3)+(2x+3)²+(x-6)^2.