Bài ôn tập chương 7 - Biểu thức đại số và đa thức một biến

Home Toán lớp 7 - Sách KNTT Bài ôn tập chương 7 - Biểu thức đại số và đa thức một biếnBài tập trung bình

{"common":{"save":0,"post_id":"5819","level":2,"total":10,"point":10,"point_extra":0},"segment":[{"id":"8609","post_id":"5819","mon_id":"1158532","chapter_id":"1158660","question":"Th\u1ef1c hi\u1ec7n phép c\u1ed9ng hai \u0111a th\u1ee9c M và N bi\u1ebft<\/p>M = $-2x^4 + 4x^3 - 3x^2 - x - 15$<\/span> <\/p>N = $5x^5-6x^4+3x-2$<\/span><\/p>","options":["A. <\/strong>$5x^5 -8x^4+4x^3-3x^2+2x-17$<\/span>","B. <\/strong>$-5x^5 -8x^4+4x^3-3x^2+2x+17$<\/span>","C. <\/strong>$5x^5 +8x^4-4x^3-3x^2-2x-17$<\/span>","D. <\/strong>$-5x^5 -8x^4-4x^3+3x^2+2x+17$<\/span>"],"correct":"1","level":"2","hint":"","answer":"M + N = ($-2x^4 + 4x^3 - 3x^2 - x - 15$<\/span> ) + ( $5x^5-6x^4+3x-2$<\/span> )<\/p>= $-2x^4+4x^3-3x^2-x-15+5x^5-6x^4+3x-2$<\/span><\/p>= $5x^5 -2x^4 -6x^4 + 4x^3 - 3x^2 -x + 3x -15 -2$<\/span><\/p>= $5x^5 - 8x^4 + 4x^3 -3x^2 + 2x - 17$<\/span><\/p>\u0110áp án \u0111úng là   A. <\/strong>$5x^5 -8x^4+4x^3-3x^2+2x-17$<\/span><\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"1","date":"2022-06-02 11:50:08","option_type":"math","len":0},{"id":"8610","post_id":"5819","mon_id":"1158532","chapter_id":"1158660","question":"Bi\u1ec3u th\u1ee9c nào sau \u0111ây là \u0111a th\u1ee9c m\u1ed9t bi\u1ebfn?<\/p>","options":["A.<\/strong> $x+y^2$<\/span>","B.<\/strong> $\\dfrac{19}{3}x^7$<\/span>","C.<\/strong> $-1+xyz$<\/span>","D.<\/strong> $3x^2+x-1$<\/span>"],"correct":"[\"2\",\"4\"]","level":"2","hint":"\u0110a th\u1ee9c m\u1ed9t bi\u1ebfn (g\u1ecdi t\u1eaft là \u0111a th\u1ee9c) là t\u1ed5ng c\u1ee7a nh\u1eefng \u0111\u01a1n th\u1ee9c c\u1ee7a cùng m\u1ed9t bi\u1ebfn; m\u1ed7i \u0111\u01a1n th\u1ee9c trong t\u1ed5ng g\u1ecdi là m\u1ed9t h\u1ea1ng t\u1eed c\u1ee7a \u0111a th\u1ee9c \u0111ó.<\/p>","answer":"Các \u0111a th\u1ee9c m\u1ed9t bi\u1ebfn là <\/p>B.<\/strong> $\\dfrac{19}{3}x^7$<\/span><\/span><\/p>D.<\/strong> $3x^2+x-1$<\/span><\/span><\/p>","type":"checkbox","extra_type":"classic-checkbox","time":"0","user_id":"131","test":"1","date":"2022-06-02 11:51:20","option_type":"math","len":0},{"id":"8611","post_id":"5819","mon_id":"1158532","chapter_id":"1158660","question":"Th\u1ef1c hi\u1ec7n phép tr\u1eeb hai \u0111a th\u1ee9c M – N , bi\u1ebft<\/p>M = $-2x^4 + 4x^3 - 3x^2 - x - 15$<\/span><\/p>N = $5x^5-6x^4+3x-2$<\/span><\/p>","options":["A. $-5x^5 - 4x^4 - 4x^3 -3x^2 + 4x + 13$<\/span><\/strong>","B. $-5x^5 + 4x^4 + 4x^3 -3x^2 - 4x - 13$<\/span><\/strong>","C. $5x^5 - 4x^4 + 4x^3 -3x^2 + 4x + 13$<\/span><\/strong>","D. $5x^5 - 4x^4 + 4x^3 +3x^2 + 4x - 13$<\/span><\/strong>"],"correct":"2","level":"2","hint":"","answer":"M – N = ($-2x^4 + 4x^3 - 3x^2 - x - 15$<\/span> ) – ( $5x^5-6x^4+3x-2$<\/span> )<\/p>= $-2x^4+4x^3-3x^2-x-15 - 5x^5+6x^4-3x+2$<\/span><\/p>= $-5x^5 -2x^4+6x^4 + 4x^3 - 3x^2 -x - 3x -15 +2$<\/span><\/p>= $-5x^5 + 4x^4 + 4x^3 -3x^2 - 4x - 13$<\/span><\/p>\u0110áp án \u0111úng là   B. $-5x^5 + 4x^4 + 4x^3 -3x^2 - 4x - 13$<\/span><\/strong><\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"1","date":"2022-06-02 11:56:33","option_type":"math","len":0}]}