= -a-b+c+a+b+c
=(-a+a) - (b-b) +(c+c)
=0-0+2c
=2c
a = ( -a -b + c ) - ( -a - b - c)
= -a + c + a + b = c
=(-a + a ) -(b-b) + ( c + c )
=0-0+2c
=2c
tick tớ nhé nha các bạn yêu quý
Cho bieu thuc : A = ( -a - b + c ) - ( -a - b -c )
a ) Rut gon A
CHO bieu thuc
B=17,58*43+57*17,58/293*A
a)tim gia tri cua bieu thuc Bkhi a=2
b)tinh gia tri a khi B=2
c)tim gia tri so tu nhien ad biet bieu thuc B co gia tri lon nhat ,gia tri lon do la bao nhieu
cho a=5 vva b-c=20 va a=b(a-c)-c(a-b) gia tri bieu thuc cua a la
thu gon roi tinh bieu tri cua bieu thuc;
d=(10-a+b)-(10-b+c)-(10-c-a)
rut gon bieu thuc
(-a-b+c) - (-a-b-c)
cho M =(-a +b)-(b+c-a)+(c-a) .Trong do b,c la so nguyen con a la so nguyen am.Chung minh rang bieu thuc M luon luon duong
rut gon bieu thuc
(-a-b+c) - (-a-b-c)-2b
rut gon bieu thuc
(-a-b+c) - (-a-b-c)-2b
tim cac dang cua x sao cho
bieu thuc A = 2x-1 co gia tri duong x
bieu thuc B = 8-2x co gia tri am
bieu thuc C=2(x+3) khong am
bieu thuc D=7(2-x)khong duong
