cho ∆abc vuông tại a, đường cao ak . a) cho ab = 15 ; ac = 20.tính ak, kb, kc. b) gọi m và d lần lượt là hình chiếu của k lên ab và ac . cm: ad.ac = kb.kc c)cm: s ∆abc = s ∆amd .sin 2 b.sin 2 c ( bằng 2 cách ) d) cm: bm = bc.cos 3 b

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I think you should buy _____  pack of mineral water instead. And you can also buy _____  snacks such as potato crisps, 3 kilos of mandarins, 2 kilos of apples, 3 bunches of bananas, ______  cookies and soft candies.

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We should decorate our living room with _____ orange banner. We also need ________  ribbons, balloons, party hats and costume.

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I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.