Question

Cho biểu thức

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

a) Rút gọn A

 

Answer 1

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

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

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

\(\Rightarrow A=2c\)

Answer 2

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

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

\(A=2c\)

Vậy \(A=2c\)

Answer 3

\(A=(-a-b-c)-(-a-b-c)\)

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

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

\(=2c\)

Vậy A = 2c

Học tốt 

Answer 4

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

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

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

\(A=2c\)