Answers:

(i) 

If x^m is at the (r + 1)th term in the expression.

T_r+1 = ⁿC_r x^n-r a^r

(ii)

If x is at the (r + 1)th term in the expression.

(1 – 2x³ + 3x⁵) (1 + 1/x)⁸ = (1 – 2x³ + 3x⁵) (⁸C₀ + ⁸C₁ (1/x) + ⁸C₂ (1/x)² + ⁸C₃ (1/x)³ + ⁸C₄ (1/x)⁴ + ⁸C₅ (1/x)⁵ + ⁸C₆ (1/x)⁶ + ⁸C₇ (1/x)⁷ + ⁸C₈ (1/x)⁸)

‘x’ is in the above expression at -2x³.⁸C₂ (1/x²) + 3x⁵.⁸C₄ (1/x⁴)

Coefficient of x = -2 (8!/(2!6!)) + 3 (8!/(4! 4!))

= -56 + 210

= 154