| Exam Board | AQA |
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| Module | AS Paper 2 (AS Paper 2) |
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| Year | 2020 |
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| Session | June |
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| Topic | Binomial Theorem (positive integer n) |
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| Type | Standard binomial expansion |
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5 Joseph is expanding \(( 2 - 3 x ) ^ { 7 }\) in ascending powers of \(x\).
He states that the coefficient of the fourth term is 15120
Joseph's teacher comments that his answer is almost correct.
Using a suitable calculation, explain the teacher's comment.