CA Foundation · Quantitative Aptitude · Differential and Integral Calculus
Evaluate ∫ (x + 1)² / x dx, for x > 0, where C is the constant of integration.
The answer is x²/2 + 2x + log x + C. Expanding the numerator and dividing by x gives x + 2 + 1/x, and integrating each term gives x²/2, 2x and log x respectively. The power rule cannot be used for 1/x.
- Ax²/2 + 2x + log x + CCorrect
- Bx²/2 + 2x − 1/x + C
- C(x + 1)³/(3x) + C
- Dx² + 2x + log x + C
Explanation
Expand: (x² + 2x + 1)/x = x + 2 + 1/x. Integrating gives x²/2 + 2x + log x + C. The option with −1/x treats 1/x as x^(−1) using the power rule, which fails for n = −1, where the result is log x.
Did you get it right without looking?
One question tells you little. A timed set on Differential and Integral Calculus shows your real accuracy, how long you take and where you lose marks.
More Differential and Integral Calculus questions
- If y = log(x² + 1) (natural logarithm), then dy/dx at x = 2 is:
- Evaluate ∫₁⁴ (3√x) dx.
- The value of ∫₁ᵉ log x dx (natural logarithm) is:
- A firm has demand p = 100 − 0.5x and total cost C(x) = 20x + 200, where p is in ₹ and x is output. A tax of ₹10 per unit is imposed on the f…
- The total cost of producing x units is C(x) = 0.5x² + 20x + 800. The output at which the average cost per unit is minimum is:
- The demand function for a product is x = 60 − 3p, where x is the quantity demanded and p is the price in ₹. The price at which total revenue…