Nhật Amy
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Bài 18: Chứng tỏ 1/ (a – b + c) – (a + c) = -b 2/ (a + b) – (b – a) + c = 2a + c 3/ - (a + b – c) + (a – b – c) = -2b 4/ a(b + c) – a(b + d) = a(c – d) 5/ a(b – c) + a(d + c) = a(b + d)
1/ 8 <!--[if gte mso 9]><xml> 2/ 12 <!--[if gte mso 9]><xml> 3/ -8 <!--[if gte mso 9]><xml> 4/ x <!--[if gte mso 9]><xml> |