\(\text{a) -b-(b-a+c) }\)
\(=-b-b+a-c\)
\(=-2b+a-c\)
\(\text{ b) -(a-b+c)-(c-a)}\)
\(=-a-b-c-c+a\)
\(=\left(-a+a\right)+\left(-b\right)+\left(-c-c\right)\)
\(=-b+\left(-2c\right)\)
\(\text{c) b-(b+a-c)}\)
\(=b-b-a+c\)
\(=-a+c\)
\(\text{ d) a-(-b+a-c)}\)
\(=a+b-a+c\)
\(=\left(a-a\right)+b+c\)
\(=b+c\)
học tốt
a) -b-(b-a+c)
= −b − b + a − c
= −2b + a − c
b) -(a-b+c)-(c-a)
= −a − b − c − c + a
= −a + a + −b + −c − c
= −b + −2c
c) b-(b+a-c)
= b − b − a + c
= −a + c
d) a-(-b+a-c)
= a + b − a + c
= a − a + b + c
= b + c