A = a + b - a + b + a - c - a - c = (a - a + a - a) + (b + b) + (-c - c) = 2b - 2c = 2.(b - c)
B = a + b - c + a - b + c - b - c + a - a + b + c = (a + a + a - a) + (b - b - b + b) + (-c + c - c + c) = 2a
A = a + b - a + b + a - c - a - c = (a - a + a - a) + (b + b) + (-c - c) = 2b - 2c = 2.(b - c)
B = a + b - c + a - b + c - b - c + a - a + b + c = (a + a + a - a) + (b - b - b + b) + (-c + c - c + c) = 2a
Bo dau ngoa ri thu gon bieu thuc
A=(a+b)-(a-b)+(a-c)-(a+c)
B=(a+b-c)+(a-b+c)-(b+c-a)-(a-b-c)
bo dau ngoac roi thu gon bieu thuc
a( b-c ) - c(b-d) +a(c+d) +bc
Bo dau ngoac va thu gon bieu thuc:
a) (a+b)(2a+b)
b) (2a-b)(a-b)
c) (2a+b)(2a-b)
Bo dau ngoac roi rut gon bieu thuc :
a) - ( -a + c - d ) - ( c- a + d )
b) - ( a + b - c + d ) + ( a - b - c - d )
c) a( b- c -d ) - a( b + c - d )
Giup minh nhe minh dang can gap
thu gon roi tinh bieu tri cua bieu thuc;
d=(10-a+b)-(10-b+c)-(10-c-a)
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!!
Rut gon bieu thuc:
A=a(2b-c)-b(a+c)-(c+b)
B=(a+3b)(c-d)-(3a-d)(b+c)-2c(b-a)+2b(a+d)
Cho bieu thuc : A = ( -a - b + c ) - ( -a - b -c )
a ) Rut gon A
rut gon bieu thuc
(-a-b+c) - (-a-b-c)