Moderate -0.8 This is a straightforward application of the binomial theorem with a small positive integer power (n=4). It requires only direct substitution into the binomial formula with no problem-solving or manipulation, making it easier than average but not trivial since students must carefully handle the coefficients and signs across five terms.
Attempt binomial expansion, including attempt at coeffs. Obtain one correct, simplified, term. Obtain a further two, simplified, terms. Obtain a completely correct expansion
$(3x - 2)^4 = 81x^4 - 216x^3 + 216x^2 - 96x + 16$ | M1, A1, A1, A1 | Attempt binomial expansion, including attempt at coeffs. Obtain one correct, simplified, term. Obtain a further two, simplified, terms. Obtain a completely correct expansion | 4 marks
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