| (1) | | | | | | | | | | | | | | | | | | | | | | | | | | | ( | 4 | x | − | 4 | ) | ( | −6 | x | − | 7 | ) | + | ( | x | + | 7 | ) | ( | x | − | 7 | ) | | | | | | | | | | | | | | | | | | | | | | | | | | |
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| (2) | | | | | | | | | | | | | | | | | | | | | | | | | ( | u | − | 10 | ) | ( | u | − | 3 | ) | + | ( | u | − | 8 | ) | ( | u | + | 2 | ) | | | | | | | | | | | | | | | | | | | | | | | | |
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| (3) | | | | | | | | | | | | | | | | | | | | | | | | | ( | a | − | 10 | ) | ( | a | + | 7 | ) | − | ( | a | + | 5 | ) | ( | a | + | 10 | ) | | | | | | | | | | | | | | | | | | | | | | | | |
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| (4) | | | | | | | | | | | | | | | | | | | | | | | | ( | −8 | z | + | 10 | ) | ( | 3 | z | + | 9 | ) | − | 3 | ( | − | z | − | 5 | ) | | | | | | | | | | | | | | | | | | | | | | | |
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| (6) | | | | | | | | | | | | | | | | | | | | | | | | | ( | r | − | 3 | ) | ( | r | + | 3 | ) | − | ( | r | + | 9 | ) | ( | r | + | 8 | ) | | | | | | | | | | | | | | | | | | | | | | | | |
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| (7) | | | | | | | | | | | | | | | | | | | | | | | | | ( | v | + | 9 | ) | ( | v | + | 10 | ) | + | ( | v | − | 2 | ) | ( | v | − | 7 | ) | | | | | | | | | | | | | | | | | | | | | | | | |
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