silemus.

25Definite integral of polynomial

Evaluate ∫02(3x2+2x) dx\displaystyle \int_0^2 (3x^2 + 2x)\,dx.

Find the antiderivative term by term: x³ + x² for 3x² + 2x. Evaluating at the limits gives (8+4) − (0+0) = 12. So ∫₀² (3x²+2x) dx = 12.

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