Find the indicated coefficient or term.
-The coefficient of $x$ in the expansion of $( 7 x + 3 ) ^ { 3 }$
A) 441
B) 189
C) 378
D) 9

Question

Quizplus · Accepted Answer

The coefficient of $x$ in the expansion of $(7x + 3)^3$ can be found using the binomial theorem. Specifically, we are looking for the term that involves $x^1$, which comes from the combination of picking one $7x$ and two $3$s from the expansion. The coefficient can be calculated as $\binom{3}{1} \cdot (7x)^1 \cdot 3^2 = 3 \cdot 7 \cdot 9 = 189$.

Find the Indicated Coefficient or Term xxx In the Expansion Of (7x+3)3( 7 x + 3 ) ^ { 3 }(7x+3)3

Find the Indicated Coefficient or Term $x$ In the Expansion Of $( 7 x + 3 ) ^ { 3 }$