If R is a region enclosed by y = f(x), y = g(x), x = a, x = b,
is it possible to have f(x) and g(x) such that
the center of gravity (x^ , y^ ) is not inside R ?
let f_n (t) =∫_0 ^∞ (dx/((x^2 +t^2 )^n ))
with n from N and n≥1
1. find a explicit form of f_n (t)
2. what is the value of
g_n (t)=∫_0 ^∞ ((t dx)/((x^2 +t^2 )^(n+1) )) ?
3. calculate ∫_0 ^∞ (dx/((x^2 +3)^4 ))
and ∫_0 ^∞ (dx/((x^2 +16)^3 ))