1)
a) ( 3x + y – z ) – ( 4x – 2y + 6z )
b) K=2x × ( -3x + 5 ) + 3x × ( 2x – 12 ) + 26x
1) a) ( 3x + y – z ) – ( 4x – 2y + 6z ) b) K=2x × ( -3x + 5 ) + 3x × ( 2x – 12 ) + 26x
By Melanie
By Melanie
1)
a) ( 3x + y – z ) – ( 4x – 2y + 6z )
b) K=2x × ( -3x + 5 ) + 3x × ( 2x – 12 ) + 26x
Đáp án: $a,$ $=-x+3y-7z$
$ b,$ $=0$
Giải thích các bước giải:
$a)(3x+y-z )-(4x-2y+6z)$
$=3x+y-z-4x+2y-6z$
$=-x+3y-7z$
$b, K=2x(-3x+5 )+3x(2x-12)+26x$
$=-6x+10x+6$$x^{2}$ $-36x+26x$
$=$$-6$$x^{2}$$+10x +6x^{2} -36x+26x$
$=0$
$a) ( 3x + y – z ) – ( 4x – 2y + 6z )\\=3x+y-z-4x+2y-6z\\=-x+3y-7z\\b) K=2x . ( -3x + 5 ) + 3x . ( 2x – 12 ) + 26x\\K=-6x^{2}+10x+6x^{2}-36x+26x=0$