Question Detail

MTH 102 MTH 102 Past Questions Objective Question

Question

Integrate ∫ x²/(x+1) dx.
Options
A x²/2 - x + ln|x+1| + C
Correct Answer
B x²/2 + x - ln|x+1| + C
C x²/2 - x - ln|x+1| + C
D x²/2 + x + ln|x+1| + C
Correct Answer

Option A is the correct answer.

Detailed Explanation

Since the degree of the numerator (2) is greater than the degree of the denominator (1), perform polynomial long division or algebraic manipulation. We can rewrite x² as (x² - 1 + 1). So, x²/(x+1) = (x²-1+1)/(x+1) = ((x-1)(x+1) + 1)/(x+1) = (x-1) + 1/(x+1). Now, integrate the simplified expression: ∫ ((x-1) + 1/(x+1)) dx = ∫ x dx - ∫ 1 dx + ∫ 1/(x+1) dx. This integrates to x²/2 - x + ln|x+1| + C.

Hint

When the degree of the numerator is greater than or equal to the degree of the denominator, perform polynomial long division or manipulate the numerator to simplify the rational expression.

Question Info