f(x) = 7 - x2 and limits x = -1 to 2
Area = ∫-12 (7 - x2) dx
= 7x - x3/3 ]-12
= (7x2 - 23 / 3) - (7(-1) - (-1)3/3)
= [(42 – 8)/3] – [(1 – 21)/3]
= (34 + 20)/3
= 54/3
Area = 18