Page 39 - Math SL HB Sem 1

BNO\II{L THEORE\I

The formuia above can be simplified:

(r-rtn = r'rt.]' t - \ ll: I
.\
\r
; bJ, \\,here b =

\ l', b+ i'j
(;) b:+ I ib'- +nb"r*b")
[ ].r lr'

\ ( 1' (n) b n(n -1\ b: n(n l\ (r-r+i)
-
lt 0
r'.
nbn-r + 6" I

Example 1: Write the expansion
of( 3x + 4y 1r

l

I
I
I
I
I

Example 2 Find the coefficient of x4 in thc expansion of 2x -l
1 )ii I
I
i

I

I

I