Question

Chứng tỏ

a( b + c ) - a( b + d ) = a( c - d) 

Answer 1

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

= ab + ac - ab - ad

= (ab - ab) + ac - ad

= ac - ad 

= a.(c - d)

Answer 2

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

\(\Leftrightarrow\)ab+ac-ab-ad=a(c-d)

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

\(\Leftrightarrow\)a(c-d)=a(c-d) (đpcm)

Answer 3

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

=> ab + ac - ab - ad = a.(c-d)

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

=> a.(c-d) = a.(c-d) (đpcm)

Answer 4

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

= ab + ac - ab - ad

= ( ab - ab ) + ac - ad

= ac - ad

= a.(c - d)

chúc bạn học giỏi !!!