{"common":{"save":0,"post_id":"7845","level":2,"total":10,"point":10,"point_extra":0},"segment":[{"id":"7817","post_id":"7845","mon_id":"1159278","chapter_id":"1159328","question":"<p>Tìm góc nh\u1ecdn α, bi\u1ebft sinα = cosα.<\/p>","options":["<strong>A.<\/strong> α = 20°","<strong>B.<\/strong> α = 45°","<strong>C.<\/strong> α = 30°","<strong>D.<\/strong> α = 60°"],"correct":"2","level":"2","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> α = 45°<\/span><\/p><p> sinα = cosα<\/p><p> sinα = sin(90° – α) <\/p><p>suy ra α = 90° – α<\/p><p>hay α = 45°.<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"127","test":"0","date":"2024-10-16 02:25:56","option_type":"txt","len":2},{"id":"7819","post_id":"7845","mon_id":"1159278","chapter_id":"1159328","question":"<p>Tính giá tr\u1ecb c\u1ee7a các bi\u1ec3u th\u1ee9c <span class=\"math-tex\">$A=3-\\sin^2 45^0+2\\cos^2 60^0-3\\cot^3 45^0$<\/span>.<\/p>","options":["<strong>A.<\/strong> 3","<strong>B.<\/strong> 0","<strong>C.<\/strong> –1","<strong>D.<\/strong> 1"],"correct":"2","level":"2","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> 0<\/span><\/p><p><span class=\"math-tex\">$A=3-\\sin^2 45^0+2\\cos^2 60^0-3\\cot^3 45^0$<\/span><\/p><p><span class=\"math-tex\">$A=3-\\dfrac{1}{2}+2.\\dfrac{1}{4}-3.1$<\/span><\/p><p><span class=\"math-tex\">$A=0$<\/span><\/p>","type":"choose","extra_type":"shape1","time":"0","user_id":"127","test":"0","date":"2024-10-16 02:29:14","option_type":"txt","len":0},{"id":"7820","post_id":"7845","mon_id":"1159278","chapter_id":"1159328","question":"<p>Tính giá tr\u1ecb c\u1ee7a các bi\u1ec3u th\u1ee9c <span class=\"math-tex\">$B=\\tan45^0.\\cos30^0.\\cot30^0-\\dfrac{1}{2}$<\/span>.<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$-\\dfrac{1}{2}$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$\\dfrac{1}{2}$<\/span>","<strong>C.<\/strong> 0","<strong>D.<\/strong> 1"],"correct":"4","level":"2","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>D.<\/strong> 1<\/span><\/p><p><span class=\"math-tex\">$B=\\tan45^0.\\cos30^0.\\cot30^0-\\dfrac{1}{2}$<\/span><\/p><p><span class=\"math-tex\">$B=1.\\dfrac{\\sqrt{3}}{2}.\\sqrt{3}-\\dfrac{1}{2}$<\/span><\/p><p><span class=\"math-tex\">$B=\\dfrac{3}{2}-\\dfrac{1}{2}$<\/span><\/p><p><span class=\"math-tex\">$B=1$<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"127","test":"0","date":"2024-10-16 02:32:04","option_type":"math","len":0}]}
