Question

3) b² (a+1)-a² (b+1); 4) (a−b) (b²-c²)-(b-c) (a²-b²).
помогите пож
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Answer 1

b² (a+1)-a² (b+1) = b²a + b² - a²b - a² = b²a - a²b = (a-b) (b²-a²). For 4), we have (a−b) (b²-c²)-(b-c) (a²-b²) = (a-b) (b²-c²) - (b-c) (a-b) (b+a) = (a-b) (b-c) (b+a) (b-c) = (a-b) (b-c)² (a+b).