![](https://rs.olm.vn/images/avt/0.png?1311)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(A=x^2+2y^2+2xy-2x+2\)
\(2A=2x^2+4y^2+4xy-4x+4\)
\(2A=x^2+4xy+4y^2+x^2-4x+4\)
\(2A=\left(x+2y\right)^2+\left(x-2\right)^2\)
\(A=\frac{\left(x+2y\right)^2+\left(x-2\right)^2}{2}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
9x2+4y2+2(3x+2y+6xy)+1
= 9x2+4y2+1+6x+4y+12xy
=(3x)2+(2y)2+12+2.3x.2y+2.2y.1+2.3x.1 (1)
Thay 3x=m,2y=n,1=p
=>(1)=m2+n2+p2+2mn+2np+2pm=(m+n+p)2
=> 9x2+4y2+2(3x+2y+6xy)+1=(3x+2y+1)2
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(x^2-4x+5+y^2+2y=\left(x^2-4x+4\right)+\left(y^2+2y+1\right)\)
\(=\left(x-2\right)^2+\left(y+1\right)^2\)
b) \(2x^2+y^2-2xy+10x+25=\left(x^2+10x+25\right)+\left(x^2-2xy+y^2\right)\)
\(=\left(x+5\right)^2+\left(x-y\right)^2\)
c) \(2x^2+2y^2=\left(x^2-2xy+y^2\right)+\left(x^2+2xy+y^2\right)=\left(x-y\right)^2+\left(x+y\right)^2\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) \(M=2x^2+2y^2\)
\(=2x^2+2y^2+2xy-2xy\)
\(=x^2+2xy+y^2+x^2-2xy+y^2\)
\(\Rightarrow M=\left(x+y\right)^2+\left(x-y\right)^2\)
b) \(N=a^2+16a+b^2+6b+73\)
\(=a^2+16a+64+b^2+6b+9\)
\(=\left(a+8\right)^2+\left(b+3\right)^2\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) Ta có: \(\left(x^2+9x+18\right)^2+2\left(x^2+9x\right)+37\)
\(=\left(x^2+9x+18\right)^2+2\cdot\left(x^2+9x+18\right)-36+37\)
\(=\left(x^2+9x+19\right)^2\)
b) Ta có: \(x^2+y^2+2x+2y+2\left(x+1\right)\left(y+1\right)+2\)
\(=\left(x^2+2x+1\right)+\left(y^2+2y+1\right)+2\left(x+1\right)\left(y+1\right)\)
\(=\left(x^2+2x+2+y^2+2y\right)^2\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a, \(\left(\frac{1}{2}+x\right)^2=\left(\frac{1}{2}\right)^2+2.\frac{1}{2}.x+x^2=\frac{1}{4}+x+x^2\)
\(\left(2x+1\right)^2=\left(2x\right)^2+2.2x.1+1^2=4x^2+4x+1\)
b, \(\left(2x+3y\right)^2=\left(2x\right)^2+2.2x.3y+\left(3y\right)^2=4x^2+12xy+9y^2\)
\(\left(0,01+xy\right)^2=\frac{1}{10000}+\frac{1}{50}xy+x^2y^2\)
c, \(\left(x+1\right)\left(x-1\right)=x^2-1\)
d, \(\left(x-2y\right)\left(x-2y\right)=\left(x-2y\right)^2=x^2-4xy+4y^2\)
\(56.64=\left(60-4\right)\left(60+4\right)=60^2-4^2\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) 2x2 + y2 - 2xy + 10x + 25
= (x2 + y2 - 2xy) + (x2 + 10x + 25)
= (x - y)2 + (x + 5)2
các bn xem đúng ko nhé mk làm bừa nên lên olm hỏi lại mọi người giúp giùm câu b) nha!!
5747568568769868986997696976968978907890780
![](https://rs.olm.vn/images/avt/0.png?1311)
a: Ta có: \(\left(x+3\right)\left(x+4\right)\left(x+5\right)\left(x+6\right)+1\)
\(=\left(x^2+9x+18\right)\left(x^2+9x+20\right)+1\)
\(=\left(x^2+9x\right)^2+38\left(x^2+9x\right)+360+1\)
\(=\left(x^2+9x\right)^2+2\cdot\left(x^2+9x\right)\cdot19+19^2\)
\(=\left(x^2+9x+19\right)^2\)
b. \(x^2+y^2+2x+2y+2\left(x+1\right)\left(y+1\right)+2\)
\(=\left(x^2+2x+1\right)+2\left(x+1\right)\left(y+1\right)+\left(y^2+2y+1\right)\)
\(=\left(x+1\right)^2+2\left(x+1\right)\left(y+1\right)+\left(y+1\right)^2\)
\(=\left(x+1+y+1\right)^2=\left(x+y+2\right)^2\)
c. \(x^2-2x\left(y+2\right)+y^2+4y+4\)
\(=x^2-2x\left(y+2\right)+\left(y+2\right)^2\)
\(=\left(x-y-2\right)^2\)
d. \(x^2+2x\left(y+1\right)+y^2+2y+1\)
\(=x^2+2x\left(y+1\right)+\left(y+1\right)^2\)
\(=\left(x+y+1\right)^2\)
![](https://rs.olm.vn/images/avt/0.png?1311)
a) 6xy^3+x^2y^6+9
= (xy^3 + 3)^2
b) x^4-2x^2y+y^2
= (x^2 - y)^2
c) x^6+25-10x^3
= (x^3 - 5)^2
a/ 6xy3+x2y6+9
= (xy3+3)2 bình phương của 1 tổng;cttq: (A+B)2
b/ x4-2x2y+y2
= (x2-y)2 bình phương của 1 hiệu; cttq (A-B)2
c/ x6+25-10x3
=(x3-5)2
\(2x^2+2y^2=2.\left(x^2+y^2\right)\)
MÌNH KHÔNG CHẮC LẮM
\(2x^2+2y^2=2x^2+2y^2+2xy-2xy\)
\(\Rightarrow\left(x^2+2xy+y^2\right)+\left(x^2-2xy+y^2\right)\)
\(\left(x+y\right)^2+\left(x-y\right)^2\) Chúc bn hok tốt