Câu hỏi của Jimin

Question

viet cac bieu thuc sau duoi dang tong:

a,(4-xy)^3

b,(0,1+xy)^3

Phạm Tuấn Đạt · Accepted Answer

$a,\left(4-xy\right)^3$

$=4^3-3.4^2xy+3.4.x^2y^2-x^3y^3$

$=64-48xy+12x^2y^2-x^3y^3$

$b,\left(0,1+xy\right)^3$

$=\left(0,1\right)^3+3.\left(0,1\right)^2xy+3.0,1.\left(xy\right)^2+x^3y^3$

$=0,001+0,03xy+0,3x^2y^2+x^3y^3$Câu trả lời: $a,\left(4-xy\right)^3$

$=4^3-3.4^2xy+3.4.x^2y^2-x^3y^3$

$=64-48xy+12x^2y^2-x^3y^3$

$b,\left(0,1+xy\right)^3$

$=\left(0,1\right)^3+3.\left(0,1\right)^2xy+3.0,1.\left(xy\right)^2+x^3y^3$

$=0,001+0,03xy+0,3x^2y^2+x^3y^3$

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