Final answer:
The expansion of the binomial (a+b)² is a perfect square trinomial a² + 2ab + b². This follows from the binomial theorem and comprises squaring the first term, doubling the product of the first and second terms, and squaring the second term.
Step-by-step explanation:
The question asks about the expansion of the binomial (a+b)², which is a perfect square trinomial. According to the binomial theorem, the expansion of (a+b)² is a² + 2ab + b². Here's a step by step explanation:
Square the first term (a²)
Multiply the first term by the second term and then double it (2ab)
Square the second term (b²)
Thus, (a+b)² simplifies to a² + 2ab + b², and this is a perfect square trinomial because it is derived from squaring a binomial.