nA|A|=1,|A^(-1)|(A^(-1)A= : C : () 0 1 -1 int a, : A : () Func(a) Func(&a) Func(*a) Func(&(*a)) 101100 : B : () 1/4 1/2 3/4 1/3 : B : () 0.25 0.33 0.50 0.40 70cm5cm 100 :C : () 100756080cm 1006972cm 100706575cm : B 101101 ( 100100 x0=(1,1)f(x)=4*x1+6*x2-2*x1^2-2*x1*x2-2*x2^2 x1= : B : () (-1/2,1) (1/2,1) (-1,1) (2,1) 64 22 : B : () 13% 16% 11% 5% : A : () Keith4AdrianDuncan Duncan2231 Billy3144 : D : () 1.Adrian 2.Duncan 3.Billy 4.Keith 1.Billy 2.Duncan 3.Adrian 4.Keith 1.Adrian 2.Billy 3.Duncan 4.Keith 1.Duncan 2.Billy 3.Adrian 4.Keith mysqllearn(student_id int,course_id int), sql : B : () select student_id,sum(course_id)from learn select student_id,count(course_id) from learn group by student_id select student_id,count(course_id)from learn select student_id,sum(course_id)from learn group by student_id DuncanDuncan KeithKeith 22 AdrianAdrian 1.Adrian 2.Duncan 3.Billy 4.Keith 1.Billy 2.Duncan 3.Adrian 4.Keith 1.Adrian 2.Billy 3.Duncan 4.Keith u : A : () n CSTCPTCP1KBC 16KBS2S 4KBC S : A : () 3KB 4KB 15KB 16KB y1=B0+B1x1+u, (,,, 4 : D : () Test.javajava() y1=B0+B1x1+u, y1=B0+B1x1+u, ( Test.javaTest.javajavajava ,,, : C : () 0000 123 No name View) select,insert,update update : A B :() ViewSelectGROUP BY,DISTINCT,LIMITHAVING Creat ViewReplace View select,insert,updateselect,insert,update GROUP BY,DISTINCT,LIMIT Replace View GROUP BY,DISTINCT,LIMITHAVING。。。。。。以下内容略