Find the area bounded by the curve y = 3x(^2) – 2x + 1, the ordinates x = 1 and x = 3 and the x-axis.
-
A.
24 -
B.
22 -
C.
21 -
D.
20
Correct Answer: Option D
Explanation
(frac{mathrm d y}{mathrm d x} = 3x^{2} – 2x + 1)
(y = int_{1} ^{3} (3x^{2} – 2x + 1) mathrm d x)
(y = [x^{3} – x^{2} + x]_{1} ^{3})
= ([3^{3} – 3^{2} + 3] – [1^{3} – 1^{2} + 1])
= (21 – 1 = 20)