\(18a^{2}\)
\(45a^{4}\)
\(135a^{4}\)
\(1215a^{2}\)
Correct answer is C
\((a + 3x)^{6}\).
The coefficient of \(x^{2}\) is:
\(^{6}C_{4}(a)^{6 - 2} (3x)^{2} = \frac{6!}{(6 - 4)! 4!} (a^{4})(9x^{2})\)
\(15 \times a^{4} \times 9 = 135a^{4}\)
Nigeria General Knowledge Questions and Answers
Puzzles Questions and Answers
Logical Reasoning Questions and Answers
Situational Judgement Questions and Answers
Microsoft Office Questions and Answers
Spatial Reasoning Questions and Answers
Data Interpretation Questions and Answers
Personality Test
Abstract Reasoning Questions and Answers
Quantitative Reasoning Questions and Answers
Numerical Reasoning Questions and Answers
Typing Speed and Accuracy Test
Verbal Reasoning Questions and Answers
See all →