Find $( x + 6 ) ^ { 3 }$ . Don t forget that $( x + 6 ) ^ { 3 }$ means ( x + 6)( x + 6)( x + 6).
A) $x ^ { 3 } + 6 x ^ { 2 } + 36 x + 216$
B) $x ^ { 3 } + 18 x ^ { 2 } + 36 x + 216$
C) $x ^ { 3 } + 18 x ^ { 2 } + 108 x + 36$
D) $x ^ { 3 } + 18 x ^ { 2 } + 108 x + 216$
E) none of these

Question

Quizplus · Accepted Answer

To expand $(x+6)^3$, we can use the binomial theorem or simply multiply it out:
\begin{align*}
(x+6)^3 &= (x+6)(x+6)(x+6)\
&= (x^2+12x+36)(x+6)\
&= x^3 + 6x^2 + 36x + 12x^2 + 72x + 216\
&= \boxed{x^3 + 18x^2 + 108x + 216}
\end{align*}

Find (x+6)3( x + 6 ) ^ { 3 }(x+6)3 Don T Forget That

Find $( x + 6 ) ^ { 3 }$ Don T Forget That