M=2x^2 + 7xy + 3xyz – 10. N=xyz + 3x^2 – 7xy. A. Tính M – N B. Tính -M- N Giúp mình với nhé. 17/10/2021 Bởi Lydia M=2x^2 + 7xy + 3xyz – 10. N=xyz + 3x^2 – 7xy. A. Tính M – N B. Tính -M- N Giúp mình với nhé.
a, $M-N$ $=2x²+7xy+3xyz-10-xyz-3x²+7xy$ $=-x²+2xyz+14xy-10$ b,$-M-N$ $=-2x²-7xy-3xyz+10-xyz-3x²+7xy$ $=-5x²-4xyz+10$ Bình luận
`a)M-N=2x^2 + 7xy + 3xyz – 10-(xyz + 3x^2 – 7xy)` `=2x^2 + 7xy + 3xyz – 10-xyz – 3x^2 + 7xy` `=-x^2 + 14xy + 2xyz-10 ` `b)-M-N=-(2x^2 + 7xy + 3xyz – 10)-(xyz + 3x^2 – 7xy)` `=-2x^2 – 7xy – 3xyz + 10-xyz – 3x^2 + 7xy` `=-5x^2 – 4xyz + 10 ` Bình luận
a, $M-N$
$=2x²+7xy+3xyz-10-xyz-3x²+7xy$
$=-x²+2xyz+14xy-10$
b,$-M-N$
$=-2x²-7xy-3xyz+10-xyz-3x²+7xy$
$=-5x²-4xyz+10$
`a)M-N=2x^2 + 7xy + 3xyz – 10-(xyz + 3x^2 – 7xy)`
`=2x^2 + 7xy + 3xyz – 10-xyz – 3x^2 + 7xy`
`=-x^2 + 14xy + 2xyz-10 `
`b)-M-N=-(2x^2 + 7xy + 3xyz – 10)-(xyz + 3x^2 – 7xy)`
`=-2x^2 – 7xy – 3xyz + 10-xyz – 3x^2 + 7xy`
`=-5x^2 – 4xyz + 10 `