mở ngoặc và rút gọn cho mình nhé(nêu các bước chi tiết) (ax+by).(cm+dn)=(cx+dy).(cm+bn) 01/07/2021 Bởi Maya mở ngoặc và rút gọn cho mình nhé(nêu các bước chi tiết) (ax+by).(cm+dn)=(cx+dy).(cm+bn)
`#AkaShi` `(ax+by)(cm+dn)-(cx+dy)(cm+bn)` `=(ax+by)(cm+dn)-(cx+dy)(cm+bn)` `=axcm+axdn+bycm+bydn-(c²mx+cxbn+dycm+dybn)` `=axcm+axdn+bycm+bydn-c²mx-cxbn-dycm-dybn` `=axcm+axdn+bycm-c²mx-cxbn-dycm` Bình luận
Đáp án: $\\$ Đề : `(ax + by) (cm + dn) – (cx + dy) (cm + bn)` `= ax (cm + dn) + by (cm + dn) -[ cx (cm + bn) + dy (cm + bn)]` `= axcm + axdn + bycm + bydn – [cxcm + cxbn + dycm + dybm]` `= axcm + axdn + bycm + by dn – [c^2 xm + cxbn + dycm + dybm]` `= axcm + axdn + bycm + bydn – c^2xm – cxbn – dycm – dybm` $\\$ Đề : `(ax + by) (cm + dn) + (cx + dy) (cm + bn)` `= ax (cm + dn) + by (cm + dn) + cx (cm + bn) + dy (cm + bn)` `= axcm + axdn + bycm + bydn + cxcm + cxbn + dycm + dybn` ` axcm + axdn + bycm + bydn + c^2xm + cxbn + dycm + dybn` Bình luận
`#AkaShi`
`(ax+by)(cm+dn)-(cx+dy)(cm+bn)`
`=(ax+by)(cm+dn)-(cx+dy)(cm+bn)`
`=axcm+axdn+bycm+bydn-(c²mx+cxbn+dycm+dybn)`
`=axcm+axdn+bycm+bydn-c²mx-cxbn-dycm-dybn`
`=axcm+axdn+bycm-c²mx-cxbn-dycm`
Đáp án:
$\\$
Đề : `(ax + by) (cm + dn) – (cx + dy) (cm + bn)`
`= ax (cm + dn) + by (cm + dn) -[ cx (cm + bn) + dy (cm + bn)]`
`= axcm + axdn + bycm + bydn – [cxcm + cxbn + dycm + dybm]`
`= axcm + axdn + bycm + by dn – [c^2 xm + cxbn + dycm + dybm]`
`= axcm + axdn + bycm + bydn – c^2xm – cxbn – dycm – dybm`
$\\$
Đề : `(ax + by) (cm + dn) + (cx + dy) (cm + bn)`
`= ax (cm + dn) + by (cm + dn) + cx (cm + bn) + dy (cm + bn)`
`= axcm + axdn + bycm + bydn + cxcm + cxbn + dycm + dybn`
` axcm + axdn + bycm + bydn + c^2xm + cxbn + dycm + dybn`