In the expansion of (a + b)^n, if the coefficient of a^3b^2 is 60, what is the value of n?
Practice Questions
1 question
Q1
In the expansion of (a + b)^n, if the coefficient of a^3b^2 is 60, what is the value of n?
5
6
7
8
C(n,3) * b^2 = 60. For n = 5, C(5,3) = 10, which does not satisfy. For n = 6, C(6,3) = 20, which does not satisfy. For n = 7, C(7,3) = 35, which does not satisfy. For n = 8, C(8,3) = 56, which satisfies.
Questions & Step-by-step Solutions
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Q
Q: In the expansion of (a + b)^n, if the coefficient of a^3b^2 is 60, what is the value of n?
Solution: C(n,3) * b^2 = 60. For n = 5, C(5,3) = 10, which does not satisfy. For n = 6, C(6,3) = 20, which does not satisfy. For n = 7, C(7,3) = 35, which does not satisfy. For n = 8, C(8,3) = 56, which satisfies.
