Binomila Theorem Question. (1 Viewer)

[.ben]

Hey.

Find the coefficient of x¹⁰ in the expansion of (x-1/x)⁶(x+1/x)⁸ .

Do you have to expand it? seems ridcululous what if it was to the power of 20?

 

[housemouse]

The way i would approach these questions would be just to write down the first three terms of each bracket and then think about it

 

[Ennaybur]

just do the general expansion, and say when x^k = x^10

then find out what a term with x to the power of some k, eg x^(2k+1)

then you say, to find k, 2k+1 = 10

etc.

i hope that helps lol

 

[housemouse]

I dont think the general expansion or whatever you call it would work here.