A.\(3a\)
B.\(6a\)
C.\(9a\)
D.\(12a\)

A.\(1 - x\)
B.\(x - 1\)
C.\(3 - x\)
D.\(x - 3\)

A.\(x =  - \dfrac{7}{2}\)
B.\(x =  - \dfrac{2}{7}\)
C.\(x = \dfrac{2}{7}\)
D.\(x = \dfrac{7}{2}\)

A.\(8\)
B.\(\dfrac{1}{8}\)
C.\( - 8\)
D.\( - \dfrac{1}{8}\)

A.\( - \dfrac{1}{2}\)
B.\( - \dfrac{1}{4}\)
C.\(\dfrac{1}{2}\)
D.\(\dfrac{1}{4}\)

A.\(2\)
B.\( - 1\)
C.\(1\)
D.\( - 2\)

A.\(\dfrac{{3{x^2} + 7{x^3} - 9x + 2}}{{{x^3} + 3x - 1}}\) 
B.\(\dfrac{{3{x^3} + 7{x^2} - 9x + 3}}{{{x^2} - 3x + 1}}\)
C.\(\dfrac{{7{x^3} + 3{x^2} - 9x + 3}}{{{x^3} + 3{x^2} - 1}}\) 
D.\(\dfrac{{3{x^3} + 7{x^2} - 9x + 2}}{{{x^2} + 3x - 1}}\)

A.\( - \dfrac{{32}}{{15}}\)
B.\(\dfrac{{32}}{{15}}\)
C.\(\dfrac{{33}}{{16}}\)
D.\( - \dfrac{{33}}{{16}}\)

A.\(\dfrac{1}{3}\)
B.\(\dfrac{1}{2}\)
C.\( - \dfrac{1}{3}\)
D.\( - \dfrac{1}{2}\)

A.phổi
B.da.
C.mang
D.hệ thống ống khí.