我是昨天向你求助题目的昨天我采纳错了,今天再帮我答一题(1)3b^2-(a^2+b^2)-b^2;(2)x+(2x-1)-(x/3+3);(3)-2(ab-3a^2)+5ab-a^2);(4)2a^2-1/2(ab+a^2)-8ab;(5)-(b-4)+4(-b-3);(6)1/2(x^2-y)+(x-y^2)+1/6(x^2+y^2)为了完成下列任务,
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/04 14:54:29
![我是昨天向你求助题目的昨天我采纳错了,今天再帮我答一题(1)3b^2-(a^2+b^2)-b^2;(2)x+(2x-1)-(x/3+3);(3)-2(ab-3a^2)+5ab-a^2);(4)2a^2-1/2(ab+a^2)-8ab;(5)-(b-4)+4(-b-3);(6)1/2(x^2-y)+(x-y^2)+1/6(x^2+y^2)为了完成下列任务,](/uploads/image/z/13393332-36-2.jpg?t=%E6%88%91%E6%98%AF%E6%98%A8%E5%A4%A9%E5%90%91%E4%BD%A0%E6%B1%82%E5%8A%A9%E9%A2%98%E7%9B%AE%E7%9A%84%E6%98%A8%E5%A4%A9%E6%88%91%E9%87%87%E7%BA%B3%E9%94%99%E4%BA%86%2C%E4%BB%8A%E5%A4%A9%E5%86%8D%E5%B8%AE%E6%88%91%E7%AD%94%E4%B8%80%E9%A2%98%EF%BC%881%EF%BC%893b%5E2-%28a%5E2%2Bb%5E2%29-b%5E2%3B%282%29x%2B%282x-1%29-%28x%2F3%2B3%29%3B%283%29-2%28ab-3a%5E2%29%2B5ab-a%5E2%29%3B%284%292a%5E2-1%2F2%28ab%2Ba%5E2%29-8ab%3B%285%29-%28b-4%29%2B4%28-b-3%29%3B%286%291%2F2%28x%5E2-y%29%2B%28x-y%5E2%29%2B1%2F6%28x%5E2%2By%5E2%29%E4%B8%BA%E4%BA%86%E5%AE%8C%E6%88%90%E4%B8%8B%E5%88%97%E4%BB%BB%E5%8A%A1%2C)
我是昨天向你求助题目的昨天我采纳错了,今天再帮我答一题(1)3b^2-(a^2+b^2)-b^2;(2)x+(2x-1)-(x/3+3);(3)-2(ab-3a^2)+5ab-a^2);(4)2a^2-1/2(ab+a^2)-8ab;(5)-(b-4)+4(-b-3);(6)1/2(x^2-y)+(x-y^2)+1/6(x^2+y^2)为了完成下列任务,
我是昨天向你求助题目的昨天我采纳错了,今天再帮我答一题
(1)3b^2-(a^2+b^2)-b^2;(2)x+(2x-1)-(x/3+3);(3)-2(ab-3a^2)+5ab-a^2);(4)2a^2-1/2(ab+a^2)-8ab;(5)-(b-4)+4(-b-3);(6)1/2(x^2-y)+(x-y^2)+1/6(x^2+y^2)
为了完成下列任务,你认为采用什么调查方式更合适?
(1)了解班级同学中那个月出生的人数最多;
(2)了解一批冷饮的质量是否合格;
(3)了解京剧在全校同学中的欢迎程度;
(4)了解全国人口的平均寿命;
我是昨天向你求助题目的昨天我采纳错了,今天再帮我答一题(1)3b^2-(a^2+b^2)-b^2;(2)x+(2x-1)-(x/3+3);(3)-2(ab-3a^2)+5ab-a^2);(4)2a^2-1/2(ab+a^2)-8ab;(5)-(b-4)+4(-b-3);(6)1/2(x^2-y)+(x-y^2)+1/6(x^2+y^2)为了完成下列任务,
1.普查(全面调查)
2.抽样调查
3.抽样调查
4.抽样调查
(1)3b^2-(a^2+b^2)-b^2;
=3b²-a²-b²-b²
=b²-a²
(2)x+(2x-1)-(x/3+3)
=x+2x-1-x/3-3
=8x/3-4
(3)-2(ab-3a^2)+5ab-a^2)
=-2ab+6a²+5ab-a²
=3ab+5a²
(4)2a^2-1/2(ab+a^2)-8ab;
=2a²-ab/2-a²/2-8ab
=3a²/2-17ab/2
(5)-(b-4)+4(-b-3)
=-b+4-4b-12
=-5b-8
(6)1/2(x^2-y)+(x-y^2)+1/6(x^2+y^2)
=x²/2-y/2+x-y²+x²/6+y²/6
=x²/2+x²/6+y²/6-y²-y/2+x
=2x²/3-5y²/6+x-y/2