Question

Tính tổng a

A=(a+b)+(c−d)−(c+a)−(b−d)

Answer 1

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

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

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

\(A=0\)

Answer 2

 A=(a+b)+(c−d)−(c+a)−(b−d)

   = a + b + c - d - c - a - b + d

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

   = 0

Answer 3

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

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

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

A = 0 + 0 + 0 + 0

A = 0 

Vậy A = 0

Answer 4

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

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

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

A=0