Question

đơn giản biểu thức:

-b-(b-a+c)

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

b-(b+a-c)

a-(-b+a-c)
 

Answer 1

a/ = -b - b + a - c = -2b + a - c

b/ = -a + b - c - c + a = b - 2c

c/ = b - b - a + c = -a + c

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

Answer 2

-b - (b - a + c)

= -b -b + a - c

= -2b + a - c 

Answer 3

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

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

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

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