Let I = ……….(i)
Let ……….(ii)
Comparing coefficients of A + C = 1 ……….(iii)
Comparing coefficients of 3A + B + 2C = 1 ……….(iv)
Comparing constants 2A + 2B + C = 1 ……….(v)
On solving eq. (iii), (iv) and (v), we get A = –2, B = 1, C = 3
Putting these values of A, B and C in eq. (ii),
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