Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
(3x-1)^2 - 16 = (3x-1)^2 - 4^2
= (3x-1-4)(3x-1+4)
= (3x-5)(3x+3)
\(\left(3x-1\right)^2-16\)
\(=\left(3x-1\right)^2-4^2\)
\(=\left(3x-1-4\right)\left(3x-1+4\right)\)
\(=\left(3x-5\right)\left(3x+3\right)\)
\(=3\left(x+1\right)\left(3x-5\right)\)
c) \(\left(x^2-y^2\right)^2=x^4-2x^2y^2+y^4\)
c) \(\left(x^2+3^2\right)^2=x^4+18x+81\)
c) \(\left(2x^2+1\right)^2=4x^4+4x^2+1\)
c) \(\left(3x-y^2\right)^2=9x^2-6xy^2+y^4\)
c) \(\left(x+2y^2\right)^2=x^2+4xy^2+4y^4\)
c) \(\left(3x\right)^2-y^2=\left(3x-y\right)\left(3x+y\right)\)
c) \(\left(2x+3y^2\right)^2=4x^2+12xy^2+9y^4\)
c) \(\left(4x-2y^2\right)^2=16x^2-16xy^2+4y^4\)
c) \(\left(4x^2-2y\right)^2=16x^4-16x^2y+4y^2\)
c) \(\left(\dfrac{1}{x}-5\right)\left(\dfrac{1}{x}+5\right)=\dfrac{1}{x^2}-25\)
c) \(\left(x-\dfrac{3}{2}\right)\left(x+\dfrac{3}{2}\right)=x^2-\dfrac{9}{4}\)
c) \(\left(\dfrac{x}{3}-\dfrac{y}{4}\right)\left(\dfrac{x}{3}+\dfrac{y}{4}\right)=\dfrac{x^2}{9}-\dfrac{y^2}{16}\)
c) \(\left(\dfrac{x}{y}-\dfrac{2}{3}\right)\left(\dfrac{x}{y}+\dfrac{2}{3}\right)=\dfrac{x^2}{y^2}-\dfrac{4}{9}\)
c) \(\left(\dfrac{x}{2}+\dfrac{y}{3}\right)\left(\dfrac{y}{3}-\dfrac{x}{2}\right)=\dfrac{y^2}{9}-\dfrac{x^2}{4}\)
c) \(\left(2x-\dfrac{2}{3}\right)\left(\dfrac{2}{3}+2x\right)=4x^2-\dfrac{4}{9}\)
c) \(\left(2x+\dfrac{3}{5}\right)\left(\dfrac{3}{5}-2x\right)=\dfrac{9}{25}-4x^2\)
c) \(\left(\dfrac{1}{2}x-\dfrac{4}{3}\right)\left(\dfrac{4}{4}+\dfrac{1}{2}x\right)=\dfrac{1}{4}x^2-\dfrac{16}{9}\)
c) \(\left(\dfrac{2}{3}x^2-\dfrac{y}{2}\right)\left(\dfrac{2}{3}x^2+\dfrac{y}{2}\right)=\dfrac{4}{9}x^4-\dfrac{y^2}{4}\)
\(299.301=\left(300-1\right)\left(300+1\right)=300^2-1^2=90000-1=89999\)
\(a\text{) }pt\Leftrightarrow\left(y^2+2y+1\right)+\left[\left(2^x\right)^2-2.2^x+1\right]=0\)
\(\Leftrightarrow\left(y+1\right)^2+\left(2^x-1\right)^2=0\)
\(\Leftrightarrow y+1=0\text{ và }2^x-1=0\)
\(\Leftrightarrow y=-1\text{ và }x=0\)
\(b\text{) }pt\Leftrightarrow\left(4x^2+4y^2+8xy\right)+\left(x^2-2x+1\right)+\left(y^2+2y+1\right)=0\)
\(\Leftrightarrow4\left(x+y\right)^2+\left(x-1\right)^2+\left(y+1\right)^2=0\)
\(\Leftrightarrow x+y=0\text{ và }x-1=0\text{ và }y+1=0\)
\(\Leftrightarrow x=1\text{ và }y=-1\)
\(\dfrac{1}{\left|x-2y\right|}\) + |\(x\) + 2y| = 4
Hay \(\dfrac{1}{\left|x-2y\right|+\left|x+2y\right|}\) = 4 vậy em nhỉ
x^2 + y^2 = (x + y +\(\sqrt{2xy}\))(x + y - \(\sqrt{2xy}\))
1. (A+B)2 = A2+2AB+B2
2. (A – B)2= A2 – 2AB+ B2
3. A2 – B2= (A-B)(A+B)
4. (A+B)3= A3+3A2B +3AB2+B3
5. (A – B)3 = A3- 3A2B+ 3AB2- B3
6. A3 + B3= (A+B)(A2- AB +B2)
7. A3- B3= (A- B)(A2+ AB+ B2)
8. (A+B+C)2= A2+ B2+C2+2 AB+ 2AC+ 2BC
* CHÚ Ý;
a/ a+b= -(-a-b) ; b/ (a+b)2= (-a-b)2 ; c/ (a-b)2= (b-a)2 ; d/ (a+b)3= -(-a-b)3 e/ (a-b)3=-(-a+b)3
(a+b)^2=a^2+2ab+b^2
(a-b)^2=a^2-2ab+b^2
a^2-b^2=(a+b)(a-b)
(a+b)^3=a^3+3a^2b+3ab^2+b^3
(a-b)^3=a^3-3a^2b+3ab^2-b^3
a^3+b^3=(a+b)(a^2-ab+b^2)
a^3-b^3=(a-b)(a^2+ab+b^2)
ok file
ok xong để đấy à