Помогите пожауста #617

Question

Помогите пожауста #617

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Answer 1

1) = -1/8

2) = 4/12 + 2/3= 1/3 + 2/3 = 3/3 = 1

3) = -9/15 + 2/3 + 4/15 = -9/15 + 10/15 + 4/15 = 5/15= 1/3