Question

Biến đổi vế trái thành phải

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)

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

Answer 1

a) a(b-c)+c(a-b)=ab-ac+ca-cb=ab-cb=b(a-c)

b) a(b-c)-b(a+c)=ab-ac-ab-bc=-ac-bc=-c(a+b)

c) a(b+c)-b(a-c)=ab+ac-ab+bc=ac+bc=c(a+b)

d) a(b-c)-a(b+d)=ab-ac-ab-ad=-ac-ad=-a(a+d)

Answer 2

a) a(b - c) + c(a - b) = ab - ac + ac - bc = ab - bc = b(a - c)

b) a(b - c) - b(a + c) = ab - ac - ab - bc = -ac - bc = (a + b). (-c)

c) a(b + c) - b(a - c) = ab + ac - ab + bc = ac + bc = (a + b)c

d) a(b - c) - a(b + d) = ab - ac - ab - ad = -ac - ad = -a(c + d)

Answer 3

a) a(b-c)+c (a-b)=ab-ac+ca-cb=cb=b(a-c)

b) a(b-c)-b(a+c)=ab-ac-ab-bc=ac-bc=-c(a+b)

c) a(b+c)-a(b(a-c)=ab+ac-ab+bc=ac+bc=c(a+b)

d) a(b-c)-a(b+d)=ab-ac-ab-ad=ac-ab-ad=ac-ad=a(a+d)