let give D= R_+ ^2 −{(0,0)} and α from R let
C_1 ={(x,y)∈ D/0<x^2 +y^2 ≤1 }
C_2 ={(x,y) ∈D / x^2 +y^2 ≥1} study the convergence of
I= ∫∫_C_1 ((dxdy)/(((√(x^2 +y^2 )) )^α )) and J=∫∫_C_2 ((dxdy)/(((√(x^2 +y^2 )) )^α )) .
f and g are 2 function C^n on [a,b] prove that
∫_a ^b f^((n)) (x)g(x)dx=[Σ_(k=0) ^(n−1) (−1)^k f^((k)) g^((n−k)) ]_a ^b +(−1)^n ∫_a ^b f(x)g^((n)) (x)dx