M= (2a-b+c)-(a-b-3c)+(-a+b)

    = 2a+b+c-a+b+3c-a+b

    = 3b+4c

\(M=\left(2a-b+c\right)-\left(a-b-3c\right)+\left(-a-b\right)\)

\(M=2a-b+c-a+b+3c-a-b\)

\(M=-b+4c\)

M=2a-b+c-a+b+3c-a+b=(2a-a-a)-(b-b)+(c+3c)=4c

\(a,A=\left(2a+b+3c\right)-\left(a-b+c\right)\)

\(=2a+b+3c-a+b-c\)

\(=a+2b-2c\)

\(b,B=\left(a+b-c\right)-\left(-2a+b-c\right)-\left(-a-b-2c\right)\)

\(=a+b-c+2a-b+c+a+b+2c\)

\(=4a+b+2c\)

\(c,C=\left(a-2b-c\right)-\left(-2a+b-c\right)-\left(-a-b-2c\right)\)

\(=a-2b-c+2a-b+c+a+b+2c\)

\(=4a-2b+2c\)

\(*B = -2a - 5b + 8a - 10b - 2b=6a -17b\\ *C=-3c+10a-2b+10c-2a-2b+7c=5a-4b+17c\)

a, (a+b)-(a-b)+(a-c)-(a+c)=[(a+b)-(b+a)]+[(a+c)-(c+a)]=0+0=0

Rút gọn biểu thức:

a) - (a - b + c ) - (-a - c + d)

= - a + b - c + a + c - d

= b - d

b) - (2a - 3b + 4c) + (a - b + 3c)

= - 2a + 3b - 4c + a - b + 3c

= - a + 2b - c.

a, =-a+b-c+a+c-d = (-a+a)+b+d+(-c+c)=0+b+d+0=b+d

b, =-2a+3b-4c+a-b+3c= (-2a+a)+(3b+-b) +(-4c+3c) = -a+-2b+-c

CHÚC BẠN HỌC TỐT.....

a,(a+2b+3c)^2-2(a+2b+3c)*(2a+b)+(2a +b) ^2 = (a+2b+3c-2a-b)²

=(-a+b+3c)²

^b,(x-1)*(x+1 ) *(x^2+1)*(x^4+1)*(x^8+1)*(x^16+1)=(x²-1)(x²+1)(x⁴-1)(x⁸+1)(x¹⁶+1)=(x⁴+1)(x⁴-1)(x⁸+1)(x¹⁶+1)=(x⁸-1)(x⁸+1)(x¹⁶+1)

=(x¹⁶-1)(x¹⁶+1)=x³²-1

a) a - b + c - (a - b + c) + 3b

= a - b + c - a + b - c +3b

= 3b

b) - (2a - b) - (b + 3a)

= -2a + b - b - 3a

= -5a

c) a(b + c) - b(a - c)

= ab + ac - ab + bc

= ac + bc

\(a,a-b+c-\left(a-b+c\right)+3b=a-b+c-a+b-c+3b\)

\(=3b\)

\(b,-\left(2a-b\right)-\left(b+3a\right)=-2a+b-b-3a=-5a\)

\(c,a\left(b+c\right)-b\left(a-c\right)=ab+ac-ab+bc=ac+bc\)

a) a - b + c - (a - b + c) + 3b

=a - b + c - a + b - c + 3b

=3b

b) - (2a - b)-(b + 3a)

=-2a-b-b-3a

=-5a-2b

c) a(b+c) - b(a-c)

=ab+ac-ba+bc

=ac+bc

=(a+b)c