Question 1 - A-Level Maths

Exam Board	CAIE
Module	P1 (Pure Mathematics 1)
Year	2023
Session	November
Topic	Binomial Theorem (positive integer n)
Type	Binomial times quadratic coefficient

Expand \(( 1 + 3 x ) ^ { 6 }\) in ascending powers of \(x\) up to, and including, the term in \(x ^ { 2 }\).
Hence find the coefficient of \(x ^ { 2 }\) in the expansion of \(\left( 1 - 7 x + x ^ { 2 } \right) ( 1 + 3 x ) ^ { 6 }\).