If the derivative of F (x) = ∫ x0 (x2-t2) f ′ (T) DT is infinitesimal equivalent to X2, then f ′ (0)=______ .

If the derivative of F (x) = ∫ x0 (x2-t2) f ′ (T) DT is infinitesimal equivalent to X2, then f ′ (0)=______ .

Let's get f ′ (x) = 2x ∫ x ∫ x ∫ x ∫ x ∫ x (x) = 2x ∫ x ∫ x ∫ x0f ′ (T) DT, we get the derivation, f ′ (x) = 2x ∫ x ∫ x ∫ x ∫ x0 ′ (T) DT, f (x) of F (x) f (x) = f (x) = ∫ x (x ∫ 0 (x2-t2-t2) f ′ (T) DT and the derivative of F (x (x (x) of F (x (x (x (x (x (x (x) x x = limx → 02F ′ (x) 1, that is, f ′ (0) = 12