integral of (2x^2+3)/x^3
Let's integrate: ∫2x2 + 3x3dx
For x ≠ 0, divide each numerator term by the power in the denominator: 2x2 + 3x3 = 2x + 3x3
ⅰ ∫2x2 + 3x3dx = ∫2xdx + ∫3x3dx
∫2xdx + ∫3x3dx
∫2xdx = 2·∫1xdx
We use ∫1xdx = ln|x|. The absolute value covers both signs of the denominator, on any interval where x ≠ 0
ⓘ The derivative of 2·ln|x| is 2x, so 2·ln|x| is an antiderivative of 2x: ∫2xdx = 2·ln|x|■A constant factor stays in front of the integral. An antiderivative of x^n is x^(n+1)/(n+1), for n ≠ -1: ∫3x3dx = ∫3x-3dx = -3x-22 = -32x2
2·ln|x| -32x2
▶Indefinite integrals are defined up to an additive constant C, so this yields: -32x2 + 2·ln|x| + C