\(∫\frac {dx}{x(x^2+1)} \ equals \)
\(log|x|-\frac 12log(x^2+1)+C\)
\(log|x|+\frac 12log(x^2+1)+C\)
\(-log|x|+\frac 12log(x^2+1)+C\)
\(\frac 12log|x|+log(x^2+1)+C\)
Let \(\frac {1}{x(x^2+1)}\) = \(\frac Ax+\frac {Bx+C}{x^2+1}\)
\(1 = A(x^2+1)+(Bx+C)x\)
Equating the coefficients of x2, x, and constant term, we obtain
A + B = 0
C = 0
A = 1
On solving these equations, we obtain
A = 1, B = −1, and C = 0
∴ \(\frac {1}{x(x^2+1)}\) = \(\frac 1x+\frac {-x}{x^2+1}\)
⇒ \(∫\)\(\frac {1}{x(x^2+1)} dx\) = \(∫\)\(\frac 1x-\frac {x}{x^2+1}dx\)
= \(log|x|-\frac 12log|x^2+1|+C\)
Hence, the correct Answer is (A).
Let \( f : (0, \infty) \to \mathbb{R} \) be a twice differentiable function. If for some \( a \neq 0 \), } \[ \int_0^a f(x) \, dx = f(a), \quad f(1) = 1, \quad f(16) = \frac{1}{8}, \quad \text{then } 16 - f^{-1}\left( \frac{1}{16} \right) \text{ is equal to:}\]
A racing track is built around an elliptical ground whose equation is given by \[ 9x^2 + 16y^2 = 144 \] The width of the track is \(3\) m as shown. Based on the given information answer the following: 
(i) Express \(y\) as a function of \(x\) from the given equation of ellipse.
(ii) Integrate the function obtained in (i) with respect to \(x\).
(iii)(a) Find the area of the region enclosed within the elliptical ground excluding the track using integration.
OR
(iii)(b) Write the coordinates of the points \(P\) and \(Q\) where the outer edge of the track cuts \(x\)-axis and \(y\)-axis in first quadrant and find the area of triangle formed by points \(P,O,Q\).
The number of formulas used to decompose the given improper rational functions is given below. By using the given expressions, we can quickly write the integrand as a sum of proper rational functions.

For examples,
