Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
bài thực hiện phép tính bạn tự làm
\(4a^2-4a+1-b^2=\left(2a-1\right)^2-b^2=\left(2a-b-1\right)\left(2a+b-1\right)\)
\(4x^3-4x^2-9x+9=4x^2\left(x-1\right)-9\left(x-1\right)\)
\(=\left(4x^2-9\right)\left(x-1\right)=\left(2x-3\right)\left(2x+3\right)\left(x-1\right)\)
Câu 11:
a: \(=10x^3-15x^2y-20xy^2-12x^2y+18xy^2+24y^3\)
\(=10x^3-27x^2y-2xy^2+24y^3\)
b: \(=4x^2+4x+1\)
1.
a) \(\left(-2x^3\right)\)\(\left(x^2+5x-\frac{1}{2}\right)\) = \(-2x^5\)\(-10x^4\) \(+x^3\)
b) (\(6x^3-7x^2\)\(-x+2\))\(:\left(2x+1\right)\)=\(3x^2-5x+2\)
2.
a) 9x(3x-y) + 3y (y-3x)=9x(3x-y)-3y(3x-y)
= (9x-3y)(3x-y)
= 3(3x-y)(3x-y)
= 3(3x-y)^2
b) \(x^3-3x^2\)\(-9x+27\)= \(\left(x^3-3x^2\right)\)\(-\left(9x-27\right)\)
= \(x^2\left(x-3\right)\)\(-9\left(x-3\right)\)
= \(\left(x^2-9\right)\left(x-3\right)\)
= \(\left(x+3\right)\left(x-3\right)\left(x-3\right)\)
= \(\left(x+3\right)\left(x-3\right)^2\)
Bài 1 ) a ) \(\left(-2x^3\right)\left(x^2+5x-\frac{1}{2}\right)\)
\(=-2x^5-10x^4+x^3\)
b ) \(\left(6x^3-7x^2+x+2\right):\left(2x+1\right)\)
\(=3x^2-5x+2\)
2 ) a ) \(9x\left(3x-y\right)+3y\left(y-3x\right)\)
\(=9x\left(3x-y\right)-3y\left(3x-y\right)\)
\(=\left(3x-y\right)\left(9x-3y\right)\)
\(=3\left(3x-y\right)\left(x-y\right)\)
b ) \(x^3-3x^2-9x+27\)
\(=\left(x^3-3x^2\right)-\left(9x-27\right)\)
\(=x^2\left(x-3\right)-9\left(x-3\right)\)
\(=\left(x^2-9\right)\left(x-3\right)\)
\(=\left(x-3\right)\left(x+3\right)\left(x-3\right)\)
Bài 1:tìm x ,biết:
a) (2x - 1)(3x + 2) - 6x(x + 1) = 0
\(\Leftrightarrow6x^2+x-2-6x^2-6x=0\)
\(\Leftrightarrow-5x=2\)
\(\Leftrightarrow x=\frac{-2}{5}\)
b) \(\left(4x-1\right)^2-\left(2x+1\right)\left(8x-3\right)=0\)
\(\Leftrightarrow16x^2-8x+1-16x^2-2x+3=0\)
\(\Leftrightarrow-10x=-4\)
\(\Leftrightarrow x=\frac{2}{5}\)
c) \(4x^2-1=2\left(2x+1\right)\)
\(\Leftrightarrow\left(2x+1\right)\left(2x-1\right)-2\left(2x+1\right)=0\)
\(\Leftrightarrow\left(2x+1\right)\left(2x-3\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}x=-\frac{1}{2}\\x=\frac{3}{2}\end{cases}}\)
2a) \(4x^2-9y^2-6y-1=4x^2-\left(3y+1\right)^2\)
\(=\left(2x-3y-1\right)\left(2x+3y+1\right)\)
b) \(4x^2-1-2x\left(2x-1\right)=\left(2x-1\right)\left(2x+1\right)-2x\left(2x-1\right)\)
\(=1.\left(2x-1\right)\)
c) \(x^2-8x-4y^2+16=\left(x-4\right)^2-4y^2\)
\(=\left(x-4-2y\right)\left(x-4+2y\right)\)
d) \(9x^2-12x-y^2+4=\left(3x-2\right)^2-y^2\)
\(=\left(3x-2-y\right)\left(3x-2+y\right)\)
e) \(4x^2+10x-5=4x^2+2.2.\frac{5}{2}x+\frac{25}{4}-\frac{25}{4}-5\)
\(=\left(2x+\frac{5}{2}\right)^2-\frac{45}{4}\)
\(=\left(2x+\frac{5+3\sqrt{5}}{2}\right)\left(2x+\frac{5-3\sqrt{5}}{2}\right)\)
Bài 2
a) 4x(x-3)-3x+9
=4x(x-3)-3(x-3)
= (x-3)(4x-3)
b) x3+2x2-2x-4
=(x3+2x2)-(2x+4)
=x2(x+2)-2(x+2)
=(x+2)(x2-2)
c) 4x2-4y+4y-1
=4x2-1
=(2x-1)(2x+1)
d) x5-x
=x(x4-1)
=x(x2-1)(x2+1)
a) 4x(x-3)-3x+9
= 4x(x-3) - 3(x-3)
= (x-3)(4x-3)
b)x3 + 2x2 - 2x - 4
= x2(x + 2) - 2(x + 2)
= (x+2)(x2-2)
c) 4x2 - 4y +4y -1
= [(2x)2-12] + (-4y+4y)
= (2x+1)(2x-1)
d) x5-x
= x(x4 - 1)
Bài 1 :
a) \(\left(x+3\right)\left(2-x\right)=2x-x^2+6-3x=-x-x^2+6\)
b) \(\left(15x^3y^2+6x^2y^3-x^2y^2\right):2x^2y^2\)
\(=x^2y^2\left(15x+6y-1\right):2x^2y^2\)
\(=\frac{15x+6y-1}{2}\)
Bài 2 :
a) \(3x^2-9x=3x\left(x-3\right)\)
b) \(3x^2-3xy-5x+5y=3x\left(x-y\right)-5\left(x-y\right)=\left(x-y\right)\left(3x-5\right)\)
Bài 3 :
a) \(x\left(x-2\right)+x-2=0\)
\(x\left(x-2\right)+\left(x-2\right)=0\)
\(\left(x-2\right)\left(x+1\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x-2=0\\x+1=0\end{cases}\Rightarrow\orbr{\begin{cases}x=2\\x=-1\end{cases}}}\)
b) \(\left(x-2\right)^2-\left(3+y\right)^2=0\)
\(\left(x-2-3-y\right)\left(x-2+3+y\right)=0\)
\(\left(x-y-5\right)\left(x+y+1\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x-y-5=0\\x+y+1=0\end{cases}\Rightarrow\orbr{\begin{cases}x-y=5\\x+y=-1\end{cases}}}\)
\(1,\\ a,\left(5x-6y\right)\left(2x^2-3xy-4y^2\right)\\ =10x^3-15x^2y-20xy^2-12x^2y+18xy^2+24y^3\\ =10x^3-27x^2y-2xy^2+24y^3\\ b,Làmtươngtự\\ 2,\\ a,4a^2-4a+1-b^2\\ =\left(4a^2-4a+1\right)-b^2\\ =\left(2a-1\right)^2-b^2\\ =\left(2a-1-b\right)\left(2a-1+b\right)\\ b,4x^3-4x^2-9x+9\\ =4x^2\left(x-1\right)-9\left(x-1\right)\\ =\left(x-1\right)\left(4x^2-9\right)\\ =\left(x-1\right)\left(2x-3\right)\left(2x+3\right)\)
bài 1 phần b kết quả bao nhiêu ạ