Toán Lớp 8: Phân tích thành nhân tử
a. ab ( a + b ) – bc ( b + c ) + ac ( a – c )
b. a ( b^2 – c^2 ) + b ( c^2 + a^2 ) + c ( a^2 + b^2 ) + 2abc
c. ( a + b ) ( a^2 – b^2 ) + ( b + c ) ( b^2 – c^2 ) + ( c – a ) ( c^2 – a^2 )
d. a^3 ( b – c ) + b^3 ( c -a ) + c^3 ( a – b )
e. a^3 ( c – b^2 ) + b^3 ( a – c^2 ) + c^3 ( b – a^2 ) + abc ( acb – 1 )
Leave a reply
Comments ( 2 )
= ab^2 + b^2c + a^2b + bc^2 + 2abc + ca(c+a)
=b^2(a+c) + b(a^2 + c^2 + 2ac) + ca(c+a)
=b^2(a+c) + b(a+c)^2 + ca(c+a)
=(c+a)[b^2 + b(a+c) + ca]
=(c+a)[b^2 + ab + bc + ca]
=(c+a)[b(b+a) + c(b+a)]
=(c+a)(b+c)(b+a)
= ab^2 + b^2c + a^2b + bc^2 + 2abc + ca(c+a)
=b^2(a+c) + b(a^2 + c^2 + 2ac) + ca(c+a)
=b^2(a+c) + b(a+c)^2 + ca(c+a)
=(c+a)[b^2 + b(a+c) + ca]
=(c+a)[b^2 + ab + bc + ca]
=(c+a)[b(b+a) + c(b+a)]
=(c+a)(b+c)(b+a)