What is the coefficient of a2b3 in the expansion of (a + b)5?
Question
What is the coefficient of a2b3 in the expansion of (a + b)5?
Solution
The coefficient of a term in the expansion of (a + b)^n can be found using the binomial theorem, which states that:
(a + b)^n = Σ (n choose k) * a^(n-k) * b^k
where the sum is from k = 0 to n, and "n choose k" is a binomial coefficient.
In this case, we want to find the coefficient of a^2b^3 in the expansion of (a + b)^5. This corresponds to the term where k = 3 (since b is raised to the power of 3).
So, we need to calculate "5 choose 3", which is:
5! / [3!(5-3)!] = (54321) / [(321)(21)] = 10
So, the coefficient of a^2b^3 in the expansion of (a + b)^5 is 10.
Similar Questions
Write the coefficient of x5in the expansion of: (a) (3 + x)6 (b) (2 − x)7 (c)
5b9(4ab5 + 3ab5 − b3)
What is the coefficient of the 4th term (𝑥2𝑦3) in the expansion of (𝑥 − 3𝑦)5a. 270b. 190c. −270d. 720
The coefficient of x5in the expansion of (2x + 5)8is:
. The expression (a2b3)(a−2b−3)=?
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.