问题 解答题

算一算!千万别出错!

(1)-t(-t)2-t3

(2)(-2a)3-(-a)-(3a)2

(3)(3xy22+(-xy)-(-4xy3);

(4)(x-1)(x2+x+1);

(5)(2x+y)(2x-y)-(2x-y)2

(6)(a-2b+c)(a+2b+c).

答案

(1)原式=-t3-t3=-2t3

(2)原式=-8a3-(-9a3)=a3

(3)原式=9x2y4+4x2y4=13x2y4

(4)由立方差公式知:(x-1)(x2+x+1)=x3-1;

(5)原式=4x2-y2-(4x2-4xy+y2)=4xy-2y2

(6)原式=(a+c)2-4b2=a2+2ac+c2-4b2

阅读理解

A WALK
Ten kilometers’ long.
Dogs and other little animals are welcome.
Meet at the school gate.
Time:7:30 a. m. Saturday morning
Want to know more?
Call Michael at 58555665
For Rent
One-bedroom apartment near No.3 High School.
Call Miss Wang for more.
Tel:68252503
9:00 a. m. - 4:30 p. m.
Every weekday
For Sale(大促销)
Come and buy school things!
All kinds of school things!
Soccer ball:¥50
Basketball:¥40
Pen:¥1. 50
Only five days, this week!
Lantian School Things Store, next to No. 1 High School
Wanted
A waitress(女招待)in a restaurant.
Work for eight hours.
Like to meet people.
¥160 a day.
Call Miss Li at 65433265 today!
From 10:00 a. m. to 10:00 p. m.
小题1:They will meet ______ at 7:30 a. m. on Saturday morning for the walk.
A.at No. 3 High SchoolB.at the school gate
C.at No. 1 High SchoolD.at a restaurant
小题2:If Li Lei wants to rent an apartment, he can call Miss Wang at _____.
A.68252503B.58555665C.65433265D.We don’t know
小题3:Kangkang has¥45. What can he buy in Lantian School Things Store?
A. A soccer ball.                             B. A basketball.
C. Some pens.                                 D. B and C.
小题4:Alice wants to be a waitress. She should call Miss Li______.
A.this weekB.on SaturdayC.todayD.every weekday
小题5:Which of the following is NOT true?
A.The walk is ten kilometres’ long.
B.You can call Miss Wang to rent a room at 3:00 p. m. on Monday.
C.Lantian School Things Store is next to No. 3 High School.
D.The waitress should work for eight hours.