Quy đồng mẫu thức của các phân thức x − 2 3(x − 1) , 5 2(x + 1) , x + 3 x 2 − 1 ta được:
A. x − 2 3(x − 1) = 2(x − 2)(x + 1) 6(x 2 − 1) , 5 2(x + 1) = 5(x + 1) 6(x 2 − 1) , x + 3 x 2 − 1 = 2(x + 3) 6(x 2 − 1)
B. x − 2 3(x − 1) = 2(x − 2) 6(x 2 − 1) , 5 2(x + 1) = 15(x − 1) 6(x 2 − 1) , x + 3 x 2 − 1 = 6(x + 3) 6(x 2 − 1)
C. x − 2 3(x − 1) = 2(x − 2)(x + 1) 6(x 2 − 1) , 5 2(x + 1) = 15(x − 1) 6(x 2 − 1) , x + 3 x 2 − 1 = 6 6(x 2 − 1)
D. x − 2 3(x − 1) = 2(x − 2)(x + 1) 6(x 2 − 1) , 5 2(x + 1) = 15(x − 1) 6(x 2 − 1) , x + 3 x 2 − 1 = 6(x + 3) 6(x 2 − 1)
x − 2 3 x − 1 = 2 x + 1 x − 2 3.2 x + 1 x − 1 = 2 x − 2 6 x 2 − 1
