interpret the definite integral ∫ (from a to b) 𝑓(𝑥) 𝑑x as area under the curve 𝑦=𝑓(𝑥) if 𝑓(𝑥)>0
understand the formula ∫(from a to b) 𝑓(𝑥)𝑑𝑥 = 𝐹(𝑏) − 𝐹(𝑎) and use it to calculate definite integrals
