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f(χ) = [ (χ^4-1+1)(1-χ)^2] / (1+χ^2) = (χ^2-1)(χ^2+1)(1-χ)^2 /(1+χ^2) + (1-χ)^2 / (1+χ^2) = (χ^2-1)(1-χ)^2 + (1+χ^2-2χ)/ (1+χ^2) =χ^4-2χ^3+2χ - 2χ / (1+χ^2) . Ολοκληρώνοντας έχουμε : χ^5/5 - χ^4 /2 +χ^2 - ln(1+χ^2) +c
f(χ) = [ (χ^4-1+1)(1-χ)^2] / (1+χ^2) =
ΑπάντησηΔιαγραφή(χ^2-1)(χ^2+1)(1-χ)^2 /(1+χ^2) + (1-χ)^2 / (1+χ^2)
= (χ^2-1)(1-χ)^2 + (1+χ^2-2χ)/ (1+χ^2)
=χ^4-2χ^3+2χ - 2χ / (1+χ^2) . Ολοκληρώνοντας
έχουμε : χ^5/5 - χ^4 /2 +χ^2 - ln(1+χ^2) +c