F.4 ..m2 maths..

1.solve the following equations,where n is a positive integer.

a ) nCn-3 = 120
b ) C2+nC1+nC0 =22

2. simplify
a ) (n+2)! / n * n!
b ) n! + (n-1)!
c )1/ (n - 1)! - 6/ (n+1)!

3.Find the value of n ,where n is a positive integer ,if the 1st term in the
expansion of (5x-2)^n in ascending powers of x is 64.

thx...!!><