∫_0^1t(f(t)dt=
=∫_0^1 [t(t+√(1-t^2))]dt
=∫_0^1 t^2dt + (1/2)∫_0^1 √(1-t^2)d(t^2)
= [t^3/3]_0^1 - [(1/2)*(2/3)*(1-t^2)^(3/2)]_0^1
= 1/3 + 1/3
= 2/3
∫_0^1t(f(t)dt=
=∫_0^1 [t(t+√(1-t^2))]dt
=∫_0^1 t^2dt + (1/2)∫_0^1 √(1-t^2)d(t^2)
= [t^3/3]_0^1 - [(1/2)*(2/3)*(1-t^2)^(3/2)]_0^1
= 1/3 + 1/3
= 2/3