Par calcul mental compléte ce qui suit (attention aux règles de priorité)
Conformément à la notation des calculatrices 3^2 signifie 3²

2×2+3^2= 2×(2+3)^2 = 2×(2+3^2) = (2×2+3)^2 =	1–2×3+5 = (1–2)×3+5 = 1–2×(3+5) = 1–(2×3+5) =
4–16/2+2^2 = 4–16/(2+2)^2 = (4–16)/2+2^2 = (4–16/2+2)^2 =	(-2)^2–6/2+4 = (-2)^2–(6/2+4) = -2^2–6/(2+4) = -2^2–6/2+4 =