(x + a)^2 - Math Central

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Quandaries & Queries

Question from a, a student:

If the 3rd , 4th, 5th terms in the expansion of (x + a)powe "n" are 720, 1080, 810 respectively, then
find the values of x, a and n.

Hi,

I can get you started

hence C₂ = 720, C₃ = 1080 and C₄ = 810. Consider the equations

C₃/C₂ = 1080/720 and C₄/C₃ = 810/1080

Penny

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