若直线3x+4y+m=0与圆C：（x-1）2+（y+2）2=1有公共点，则实数m_爱下问搜题

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问题填空题

若直线3x+4y+m=0与圆C：（x-1）²+（y+2）²=1有公共点，则实数m的取值范围是______．

答案

圆C：（x-1）²+（y+2）²=1，圆心坐标（1，-2），半径为：1；

当直线3x+4y+m=0与圆有公共点时，圆心到直线的距离小于等于半径可得：

|3-8+m|

32+42

≤1，

解得0≤m≤10

故答案为：[0，10]

解答题

已知点A、B、C、D的坐标分别为A（3，0）、B（0，3）、C（cosα，sinα），D（-2cosα，-t），α∈（

）．
（1）若|

|，求角α的值；
（2）若

2sin2α+2sinαcosα

的值．
（3）若f(α)=

-t2+2在定义域α∈（

）有最小值-1，求t的值．

完形填空

Long ago there was a poor farmer in Russia. He had been very 1 with everything he had. However, when he found his elder brother was 2 than him, he felt disappointed. So he 3 hard about how he could also be richer. Finally he got an idea. He started to spend less money on food and clothes to 4 some money to buy more land. Once he had enough money, he started 5 for land.
He 6 that on the neighboring land, there were some nomads (游牧民) living there. He bought some gifts and went to 7 their head. He presented the gifts to the head and told him the 8 of his visit. The head welcomed him, accepted the gifts and agreed to his 9 to get the land. The head told him that he could have the land 10 giving him anything. He can take as much land as he could 11 by walking through the land before sunset (日落). He should start in the morning and whatever distance he could travel during the 12 , he could have it.
The farmer became very 13 when he heard this offer. Now he could have lots of 14 without paying anything. He came 15 the next morning and started running, not walking, 16 he could cover the largest area. To reach his goal, he neither ate food, nor drank water, nor had any rest. He just continued 17 . Without eating, or drinking, or resting he just got very 18 . When he came back to the head in the evening, he 19 right on the spot. Sadly his son buried him in a piece of land about 6 x 4 feet.
Don’t be greedy (贪婪的) or you will 20 everything finally.