Đề chính thức
– Chuyên Toán – Tin –
Thời gian làm bài: 150 phút (không kể thời gian phát đề)
1 1 x y x y .
A x y x y x y
A x 2021 2 505 y 2021 2 505 , , 0
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10 101 102 A
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a b 2021 2021 2021 2021 2021 2021 2021
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IG BC E D BC
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PB QB. 1
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6
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3 12 3 2 39 39 231
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