\(\frac {1}{x(x^4-1)}\)
Multiplying numerator and denominator by x3 , we obtain
\(\frac {1}{x(x^4-1)}\) = \(\frac {x^3}{x^4(x^4-1)}\)
∴ \(∫\)\(\frac {1}{x(x^4-1)}dx\) = \(∫\)\(\frac {x^3}{x^4(x^4-1)}dx\)
Let x4 = t ⇒ 4x3dx = dt
∴ \(∫\)\(\frac {1}{x(x^4-1)}dx\) = \(\frac 14∫\frac {dt}{t(t-1)}\)
Let \(\frac {1}{t(t-1)}\) = \(\frac At+\frac {B}{(t-1)}\)
\(1 = A(t-1) + Bt \) ...(1)
Substituting t = 0 and 1 in (1), we obtain
\(A = -1\ and \ B = 1\)
⇒ \(\frac {1}{t(t-1)}\) = \(\frac {-1}{t}+\frac {1}{t-1}\)
⇒ \(∫\)\(\frac {1}{x(x^4-1)}dx\) = \(\frac 14\) \(∫\)\(\frac {-1}{t}+\frac {1}{t-1}dt\)
= \(\frac 14[-log|t|+log|t-1|]+C\)
= \(\frac 14log\ |\frac {t-1}{t}|+C\)
= \(\frac 14log|\frac {x^4-1}{x^4}|+C\)
Let \( f : (0, \infty) \to \mathbb{R} \) be a twice differentiable function. If for some \( a \neq 0 \), } \[ \int_0^a f(x) \, dx = f(a), \quad f(1) = 1, \quad f(16) = \frac{1}{8}, \quad \text{then } 16 - f^{-1}\left( \frac{1}{16} \right) \text{ is equal to:}\]
The probability of hitting the target by a trained sniper is three times the probability of not hitting the target on a stormy day due to high wind speed. The sniper fired two shots on the target on a stormy day when wind speed was very high. Find the probability that
(i) target is hit.
(ii) at least one shot misses the target. 
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,
