let f(x) =∫_0 ^1 ln(1−xt^3 )dt with ∣x∣<1
1) find a explicit form of f(x)
2)calculate ∫_0 ^1 ln(1−(1/(√2))t^3 )dt
3) calculate A(θ) =∫_0 ^1 ln(1−sinθ t^3 )dt with 0<θ<(π/2)
let I =∫_(−∞) ^(+∞) (dx/((x+i)^n )) and J =∫_(−∞) ^(+∞) (dx/((x−i)^n ))
1) calculate I and J interms of n
2) find thevalue of integral
A_n =∫_(−∞) ^(+∞) (( cos(narctan((1/x))))/((1+x^2 )^(n/2) ))dx
let f_n (a) =∫_(−∞) ^(+∞) ((cos(nx))/((x^2 +x +a)^2 ))dx with a≥1
1) find a explicit form of f_n (a)
2)study the convervenge of Σ f_n (a)
3) determine also g_n (a) = ∫_(−∞) ^(+∞) ((cos(nx))/((x^2 +x+a)^3 ))dx
study the convergence of Σ gn(a)