A:π6
B:π3
C:-π6
D:-π3
①x3+2xy+x=x(x2+2y);②x2+4x+4=(x+2)2;③﹣x2+y2=(x+y)(x﹣y)
1米12就是1米1分米2厘米.
那么,2米90就是____米____分米____厘米.
– How do you study _______ a test?
-- I study working with a group.
I’m against____ (build) bridge over the river.