一、填空题(本大题共12小题,每小题2分,满分24分)1.-2的倒数是.2.比较大小:-31-12(填“”或“”)3.成熟的红细胞没有细胞核,呈两面凹的圆形饼状,平均直径只有7.7微米(1微米=0.01毫米).用科学记数法表示7.7微米=米.4.在函数y=樤２-x+1樤x-1中,自变量x的取值范围是.5.计算:cot3 I. Fill in the blanks (a total of 12 questions in this big question, 2 points for each question, out of 24 points) 1. The reciprocal of 1.-2 is. 2. Compare the size: -31-12 (fill in “” or “”) 3. Mature erythrocytes have no nuclei and are two-concave, circular pies with an average diameter of only 7.7 microns (1 micron = 0.01 millimeters). Scientific notation is 7.7 micrometers = m. 4. In the function y = 樤 2-x + In 1樤x-1, the range of the independent variable x is .5. Calculation: cot3