Question

biến đổi vế trái thành vế phải . nhanh nha cách giải luôn đo

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

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

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

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

help me

Answer 1

a) Ta có: \(a\left(b-c\right)+c\left(a-b\right)\)

\(=ab-ac+ac-bc\)

\(=ab-bc\)

\(=b\left(a-c\right)\)(đpcm)

b) Ta có: \(a\left(b-c\right)-b\left(a+c\right)\)

\(=ab-ac-ab-bc\)

\(=-ac-bc\)

\(=\left(-c\right)\cdot\left(a+b\right)=\left(a+b\right)\cdot\left(-c\right)\)(đpcm)

c) Ta có: \(a\left(b+c\right)-b\left(a-c\right)\)

\(=ab+ac-ab+bc\)

\(=ac+bc\)

\(=\left(a+b\right)\cdot c\)(đpcm)

d) Sửa đề: \(a\left(b-c\right)-a\left(b+d\right)\)

Ta có: \(a\left(b-c\right)-a\left(b+d\right)\)

\(=ab-ac-ab-ad\)

\(=-ac-ad\)

\(=-a\left(c+d\right)\)(đpcm)

Answer 2

https://i.imgur.com/4h00NKr.jpg