viet cac bieu thuc sau duoi dang tong
(x+2y)^3
(2x-y)^3
(_5a-b)^3
viet cac bieu thuc sau duoi dang tong:
a,(4-xy)^3
b,(0,1+xy)^3
\(a,\left(4-xy\right)^3\)
\(=4^3-3.4^2xy+3.4.x^2y^2-x^3y^3\)
\(=64-48xy+12x^2y^2-x^3y^3\)
\(b,\left(0,1+xy\right)^3\)
\(=\left(0,1\right)^3+3.\left(0,1\right)^2xy+3.0,1.\left(xy\right)^2+x^3y^3\)
\(=0,001+0,03xy+0,3x^2y^2+x^3y^3\)
viet cac bieu thuc sau duoi dang tich: x^3 y^3+225
\(x^3y^3+125=\left(xy+5\right)\left(x^2y^2-5xy+25\right)\)
1. viet cac bieu thuc sau duoi dang tong
a) (2x+3y)2 ; (0,01+xy)2
b) (x-2y).(x-2y) ; (56.64)
c) (x-y+z).(x+y+z)
d) (x+y+z).(x-y-z)
e) (x+1).(x-1)
CMR bieu thuc sau viet duoc duoi dang tong cac binh phuong cua hai bieu thuc
x2+2(x+1)2+3(x+2)2+4(x+3)2
viet cac bieu thuc sau duoi dang tong:
a,(-3x+2)\(^3\)
\(a,\left(-3x+2\right)^3\)
\(=\left(2-3x\right)^3\)
\(=2^3-3.2^2.3x+3.2.9x^2-27x^3\)
\(=8-36x+54x^2-27x^3\)
viet cac bieu thuc sau duoi dang tong:
a,(-3x+2)\(^3\)
\(a,\left(-3x+2\right)^3=\left(2-3x\right)^3=2^3-3.2^2.3x+3.2.9x^2-27x^3=8-36x+54x^2-27x^3\)
viet cac bieu thuc sau duoi dang tich;
a,x\(^3\)y\(^3\)+225
Câu a : \(x^3y^3+225=\left(xy\right)^3+\left(\sqrt[3]{225}\right)^3=\left(xy+\sqrt[3]{225}\right)\left(x^2y^2-xy\sqrt[3]{225}+\left(\sqrt[3]{225}\right)^2\right)\)
Chúc bạn học tốt
viet cac bieu thuc sau duoi dang tich;
a,x\(^3\)y\(^3\)+225
\(x^3y^3+255=\left(xy+\sqrt[3]{225}\right)\left(x^2y^2-xy\sqrt[3]{225}+\sqrt[3]{225^2}\right)\)
viet cac bieu thuc sau duoi dang tich:
a, -64+(x-3)\(^3\)
\(a,\left(-64\right)+\left(x-3\right)^3\)
\(=\left(-4\right)^3+\left(x-3\right)^3\)
\(=\left(-4+x-3\right)\left[\left(-4\right)^2-\left(-4\right)\left(x-3\right)+\left(x-3\right)^2\right]\)