Def: Fie 𝐹, 𝑓: 𝐼 → ℝ , 𝐼 ⊆ ℝ , 𝐼 interval. 𝐹 este o primitivă pentru 𝑓 dacă: 𝐹′ (𝑥 ) = 𝑓 (𝑥 ), ∀𝑥 ∈ 𝐼. Primitive uzuale ∫ 1 𝑑𝑥 = 𝑥 + 𝒞 ∫ 𝑥 𝑝 𝑑𝑥 = 𝑥 𝑝+1 𝑝+1 + 𝒞, 𝑝 ≠ −1 1 ∫ 𝑑𝑥 = ln|𝑥| + 𝒞 𝑥 𝑎𝑥 ∫ 𝑎𝑥 𝑑𝑥 = + 𝒞, 𝑎 > 0, 𝑎 ≠ 1; ∫ 𝑒 𝑥 𝑑𝑥 = 𝑒 𝑥 + 𝒞 ln 𝑎 ∫ sin 𝑥 𝑑𝑥 = − cos 𝑥 + 𝒞 ∫ cos 𝑥 𝑑𝑥 = sin 𝑥 + 𝒞 ∫ 𝑡𝑔 𝑥 𝑑𝑥 = − ln|cos 𝑥| + 𝒞 ∫ 𝑐𝑡𝑔 𝑥 𝑑𝑥 = ln|sin 𝑥| + 𝒞 1 ∫ 2 𝑑𝑥 = 𝑡𝑔 𝑥 + 𝒞 cos 𝑥 1 ∫ 2 𝑑𝑥 = −𝑐𝑡𝑔 𝑥 + 𝒞 sin 𝑥 1 𝑥 ∫ 2 2 𝑑𝑥 = 𝑎𝑟𝑐𝑠𝑖𝑛 + 𝒞 √𝑎 −𝑥 𝑎 1 ∫ 2 𝑑𝑥 = ln|𝑥 + √𝑥 2 + 𝑎| + 𝒞, 𝑎 ≠ 0 √𝑥 +𝑎 1 1 𝑥 1 1 𝑥−𝑎 ∫ 2 2 𝑑𝑥 = 𝑎𝑟𝑐𝑡𝑔 + 𝒞, 𝑎 > 0 𝑥 +𝑎 𝑎 𝑎 ∫ 2 2 𝑑𝑥 = ln | | + 𝒞 𝑥 −𝑎 2𝑎 𝑥+𝑎 Reguli: ∫ 𝑎 ⋅ 𝑓 (𝑥 ) 𝑑𝑥 = 𝑎 ⋅ ∫ 𝑓(𝑥 ) 𝑑𝑥 ∫[𝑓 (𝑥 ) + 𝑔(𝑥)] 𝑑𝑥 = ∫ 𝑓(𝑥 )𝑑𝑥 + ∫ 𝑔(𝑥 )𝑑𝑥