Question

The coefficient of x in the expansion of (x + 3)³ is
(a) 1
(b) 9
(c) 18
(d) 27

Answer 1

(x + 3)³
$$\begin{gathered} =x^3+3^3+9x\left(x+3\right) \\ =x^3+27+9x^2+27x \end{gathered}$$
So, the coefficient of x in (x + 3)³ is 27.
Hence, the correct answer is option (d).