Prerequisite: Ensure deg(P) < deg(Q). If not, perform polynomial long division first.
Type 1: Distinct Linear Factors Q(x) = (x-a)(x-b)(x-c)... P/Q = + + Cover-up method: A = P(a)/[Q] evaluated at x = a.
Type 2: Repeated Linear Factors Q(x) = (x-a)^n P/Q = + ^2 + ... + ^n Find by cover-up at x = a. Find others by comparing coefficients or differentiating.
Type 3: Irreducible Quadratic Factor Q(x) = (x-a)() where has no real roots P/Q = + The quadratic term integrates to: aln|| + barctan form (after completing the square).
Integration After Decomposition:
- integrates to A*ln|x-a|
- ^n integrates to A/[(1-n)(x-a)^(n-1)] for n > 1
- : split as * + , giving logarithm + arctan terms
JEE Shortcut for (x-b)): Write px+q = L(x-a) + M(x-b). Then L = , M = . Integral = Lln|x-a| + Mln|x-b| + C.