The coefficient of x² in1+x²/(1-x)³ is

If p and q are the coefficients of xⁿ in (1+x)^2n-1 and (1+x)²ⁿ respectively then 2p=

C₀+C₁/2+C₃/3+ …………C_n/n+1+ =

The positive integer which is just greater than (1+0.0001)¹⁰⁰⁰⁰ is

The coefficient of x¹⁰ in 1-2x+3x²/1-x is