Question

Khai triển các biểu thức:

a) (a-b+c)²                               b) (a+2b-c)²

c) (2a-b-c)²

Answer 1

a, \(\left(a-b+c\right)^2=a^2+b^2+c^2-2ab-2bc+2ca\)

Answer 2

b, \(\left(a+2b-c\right)^2=a^2+4b^2+c^2+4ab-4bc-2ca\)

Answer 3

c, \(\left(2a-b-c\right)^2=4a^2+b^2+c^2-4ab+2bc-4ca\)

Answer 4

a: \(\left(a-b+c\right)^2=a^2+b^2+c^2-2ab-2bc+2ac\)

b: \(\left(a+2b-c\right)^2=a^2+4b^2+c^2+4ab-2ac-4bc\)

c: \(\left(2a-b-c\right)^2=4a^2+b^2+c^2-4ab-4ac+2bc\)