题目内容
下列计算错误的是
A.
(a-2)3=a-6
B.
(a2)3=a5
C.
a2÷a3=a-l
D.
a3·a2=a5
计算:812n-1·3n-1=________.
填空:
(1)( )·28=216;
(2)( )·53=55;
(3)( )·105=107;
(4)( )·a3=a6.
用科学记数法表示:
8684000000=________;-8080000000=________.
(-1)0=1
(-1)-1=-1
(-x)7÷(-x)3=x4
4-2=________,(-x)-3=________.
下列计算正确的是
m3+m2=m5
m3·m2=m6
(1-m)(1+m)=m2-1
=
已知当x=1时,2ax2+bx的值为3,则当x=2时,ax2+bx的值为________.
下列各式计算正确的是
(a+4)(a-4)=a2-4
(2a+3)(2a-3)=2a2-9
(5ab+1)(5ab-1)=25a2b2-1
(a+2)(a-4)=a2-8