Cho K=(x+1/x-1-x-1/x+1+x^2-4x-1/x^2-1).(x+2003)/x Rút gọn K.
Giải thích
Ta có K=(x+1)2−(x−1)2+x2−4x−1(x−1)(x+1)⋅x+2003x=x2+2x+1−x2+2x−1+x2−4x−1(x−1)(x+1)⋅x+2003x=x2−1x2−1⋅x+2003x=x+2003x
Ta có K=(x+1)2−(x−1)2+x2−4x−1(x−1)(x+1)⋅x+2003x=x2+2x+1−x2+2x−1+x2−4x−1(x−1)(x+1)⋅x+2003x=x2−1x2−1⋅x+2003x=x+2003x