(1đ) Cho số phức z1 z2 thỏa |z1 + z2|2 + |z1 - z2|2 = (|z1| + |z2|)2 Chứng minh |z1| =|z2| (1đ) Cho hàm số: y = x3 – 2x + (C) Viết PTTT (C) a Tại điểm có hồnh độ x = b Biết tiếp tuyến qua gốc tọa độ O (1đ) Cho hàm số y = x4 – (m+4)x2 + m2 + 3, có đồ thị (C) Tìm m để (C) giao Ox bốn điểm phân biệt x1,x2,x3,x4 thỏa mãn x14+x24+x34+x44 =50 (1đ) Viết CTCT chất sau: a 1-etyl-1,2,4-trimetylxiclobutan b 6-etyl-4,7-đimetyl-3-propyloct-2-en c 4,5-đimetylheptan-2,3-điol d trans-pent-2-en e Naphtalen (1đ) Hỗn hợp X chứa a.cacboxylic đơn, hởm gồm axit no hai axit không no có liên kết đơi (C=C) Cho m gam X tác dụng vừa đủ với 150ml dd NaOH 2M, thu 25.56 gam hh muối Đốt cháy hoàn toàn m gam X, hấp thụ toàn sản phẩm cháy dd NaOH dư, khối lượng bình tăng 40.8g Tính tổng khối lượng a.cacboxylic không no (0.75đ) Một vật nặng có khối lượng M = 600g đặt phía lị xo thẳng đứng có k = 200 (N/m) Khi VTCB, thả vật m = 200g từ độ cao h = 6cm so với M Coi va chạm hoàn toàn mềm Lấy g = 10 (m/s2), π2 = 10 Tính: a Vận tốc m trước va chạm A b Vận tốc hai vật sau va chạm c Sau va chạm hai vật dao động điều hòa với biên độ (0.5đ) Một lắc đơn có khối lượng m1 = 400g, có chiều dài 160cm, ban đầu người ta kéo vật lệch khỏi VTCB góc 60° thả nhẹ cho vật dao động, vật qua VTCB vật va chạm mềm với vật m2 = 100g đứng yên, lấy g = 10 (m/s2) Tính biên độ góc lắc đơn sau va chạm (0.75đ) Hai nguồn âm nhỏ S1, S2 giống (được coi hai nguồn kết hợp) phát âm pha và biên độ Một nguời đứng điểm N với S1N = 3m, S2N = 3,375m Tốc độ truyền âm khơng khí 330m/s Tìm bước sóng dài để người N khơng nghe âm từ hai nguồn S1, S2 phát (0.75đ) Ở loài động vật, cho giao phối đực (XY) (XX) có lơng đỏ thu F1 có tỉ lệ đỏ : trắng (lông trắng xuất cái) Chọn cặp lông đỏ F1 cho giao phối với Tính xác suất cá thể lơng đỏ F2 (0.25đ) Cho P tự thụ phấn thu 11 thân cao, đỏ: thân cao vàng : thân thấp, đỏ Biết D quy định đỏ, d quy định vàng Tìm kiểu gen P 1đ) Read the passage and the task that follows Aircraft capable of flying at ten times the speed of sound are being designed for the future They will take off from an ordinary runway, climb through the atmosphere to the edge of their destination One day in the 21st century, people will be landing in Tokyo just one hour after taking off from Heathrow Airport in London Most of our energy comes from coal, oil and gas One day these fossil fuels will all be consumed We should be careful now how we use them and make plans for using less Our attitudes to energy in the next 20 years will affect the entire planet for centuries Generating electricity from the wind is a good, clean source of energy to come, but an intrusion on the landscape to others One critic described them as "like toilet brushes disfiguring the countryside." Tropical forests are immensely rich They may cover only six per cent of the earth's surface, but they support over two-thirds of the world's plant and animal species Scientists believe that a quarter of a million plant species could be made extinct in our children's life time largely because of forest destruction The forests are a vital source of medicinal plants and so by destroying forests, we may be destroying the drugs which could cure cancer and other serious diseases In the time it takes you to this exercise, four more species will have become extinct More than three-quarters of the world's fresh water is locked in the ice-caps of the Artic and Antarctica A small amount of this pure water would be sufficient to transform the dry areas of the world into fertile land Engineers think that it would be possible to transport an iceberg of up to 10 kilometres in length using a tug the size of a supertanker to pull it The Sahara desert has the advantage of being close to the sea and could be irrigated using water from the iceberg without the expense of long-distance pipelines Pedestrians in the cities of the future could speed through the streets at up to 15 kilometres per hour just by standing still A network of moving pavements could reduce travelling time and end rush-hour traffic jams forever A Swiss company has invented a system of high speed moving pavements Pedestrians will be able to step on and off them as easily as using an ordinary escalator Most people would be happy to find a way to stay younger longer and scientists have been working on experiments with hormonal treatments and chemicals to reduce the oxygen content of the blood But the most promising method of retarding age is through diet Research has shown that a diet containing all the essential ingredients but with the calorie intake reduced to only three-fifths the normal level could lead to a lifespan of two-fifths longer a In the 21th century, humans will be living longer Research has shown that the best way to delay the ageing process is by b By the beginning of the 21th century, boats may be transporting enormous icebergs from the south Atlantic _ c In the future pedestrians will be getting around town more quickly _ d It will be possible to get from London to Tokyo by space aircraft _ (1đ) Find out the underline part that needs correcting People respected (A) him because (B) he was a (C) honest man (D) My mother is responsible (A) to (B) the household chores in (C) my (D) family This (A) room has not been used (B) since (C) a (D) long time My children won’t go (A) to bed unless (B) they don’t have (C) some (D) money ... and the task that follows Aircraft capable of flying at ten times the speed of sound are being designed for the future They will take off from an ordinary runway, climb through the atmosphere to... you to this exercise, four more species will have become extinct More than three-quarters of the world's fresh water is locked in the ice-caps of the Artic and Antarctica A small amount of this... Artic and Antarctica A small amount of this pure water would be sufficient to transform the dry areas of the world into fertile land Engineers think that it would be possible to transport an iceberg