Rút gọn biểu thức sau
Rút gọn biểu thức sau:
a) ( x-1 )^3 - ( x-1 ).( x^2+x+1 )
b) ( x-3 )^3 - ( x-3 ).( x^2+3x+9 ) + 6( x+1 )^2
c) ( x+5 ).( x^2-5x+25 ) - ( x+3 )^3 + ( x-2 ).( x^2+2x+4 )-(x-1)^3
d) ( 3x-2x )^3 - ( 4x-5y ).( 16x^2+20xy+25y^2 ) + ( y+2x )^3
a) ( x-1 )^3 - ( x-1 ).( x^2+x+1 )
b) ( x-3 )^3 - ( x-3 ).( x^2+3x+9 ) + 6( x+1 )^2
c) ( x+5 ).( x^2-5x+25 ) - ( x+3 )^3 + ( x-2 ).( x^2+2x+4 )-(x-1)^3
d) ( 3x-2x )^3 - ( 4x-5y ).( 16x^2+20xy+25y^2 ) + ( y+2x )^3