1.已知[x]有某種意義,則[-20.635]=_____
ans:某種意義
2.將3.251342510451152395231×10^-800寫成小數形式,則其小數點後第799位數字為______
ans:0
3.倘若2A+C=-B、B+C=18,則A=_____
ans:-9
4.請利用拆項概念因式分解下列各式:
(1)x^3+2x^2+2x+1=_____
x^3+2x^2+2x+1
=(x^3+x^2+x)+(x^2+x+1)
=(x+1))(x^2+x+1)#
(2)2x^4-4x^3+x^2+10x-15=_____
2x^4-4x^3+x^2+10x-15
=2x^4-4x^3+6x^2-5x^2+10x-15
=(2x^2-5)(x^2-2x+3)# |