Rút gọn biểu thức P={((x-căn x+2)/((căn x+1)(căn x-2))-(x/(căn x(căn x-2))}/((1- căn x)/(2-căn x))
Giải thích
Ta có:P=x−x+2(x+1)(x−2)−xx(x−2):1−x2−x=x−x+2−x(x+1)(x+1)(x−2).2−x1−x=2−2x(x+1)(x−1)=2(1−x)(x+1)(x−1)=−2x+1
Ta có:P=x−x+2(x+1)(x−2)−xx(x−2):1−x2−x=x−x+2−x(x+1)(x+1)(x−2).2−x1−x=2−2x(x+1)(x−1)=2(1−x)(x+1)(x−1)=−2x+1