x+2x+4x+...+125x+126x bang cach thu gon cac bieu thuc sau:
cho bieu thuc A = /x-1/ + 3x-7
a. rut gon bieu thuc
b. tinh A khi x=3;x=-5
Thu gon bieu thuc sau roi tim gia tri cua x de bieu thuc co gia tri la so am
7 × -19 × x + 6 × x
thu gon bieu thuc sau:
135.234+135.324-135.556
thu gon roi tinh bieu tri cua bieu thuc;
d=(10-a+b)-(10-b+c)-(10-c-a)
Thu gon cac bieu thuc sau
7x - 19x + 6x
-ab - ab
thu gon bieu thuc
cho A = 1+3+ 32 +33+ ... + 32015
bo dau ngoac roi thu gon bieu thuc
a( b-c ) - c(b-d) +a(c+d) +bc
B1: Thu gon cac bieu thuc
a/ A=(a+b-c)-(2b+c-a)+(-2a+3b+4c)
b/ B=a.(a-b+c)-b.(b-c-a)-bc+a^2-b^2
c/ C= -2.(x-y)+3.(y+x)+4x-5y
Giúp mình với nhé!!