Tìm GTNN:
A=5x^2 -x +2
B=3x^2 -y+2y^2+x-11
Những câu hỏi liên quan
18 tháng 3 2022 lúc 9:10
tìm đa thức M
a M + (5x^2 - 2xy) = 6x^2 + 9xy - y^2
b (25 x^2y-13xy^2 + y^3)-M= 11 xy^2 - 2y^3
\(a,M+\left(5x^2-2xy\right)=6x^2+9xy-y^2\\ \Rightarrow M=6x^2+9xy-y^2-5x^2+2xy\\ \Rightarrow M=x^2+11xy-y^2\\ b,\left(25x^2y-13xy^2+y^3\right)-M=11xy^2-2y^3\\ \Rightarrow M=25x^2y-13xy^2+y^3-11xy^2+2y^3\\ \Rightarrow M=25x^2y-24xy^2+3y^3\)
Đúng 1
Bình luận (0)
Question Expandand simplify: 1. 8(x+5)-3(2x+7)
2. a(2b+c)+b(3c-2a)
3. 2y(y+5x)+x(3x+4y)
answer , 1. 8(x+5)-3(2x+7)=8x+40-6x+21=2x+61
2. a(2b+c)+b(3c-2a)=2ab+ac+3bc-2ab=ac+3bc=3abc^(2)
3. 2y(y+5x)+x(3x+4y)=2y^(2)+10xy+9x^(2)+4xy=9x^(2)+2y^(2)+14xy
a Explain what he has done wrong.
b work out the correct answer
1)5x^2y-30xy^2+45y^3 2)x^4-3x^3-24x+8 3)x^2(y-z)+y^2(z-x)+z^2(x-y) 4)6a^2-ab-2b^2+3a-2b
2: Ta có: \(x^4-3x^3-24x+8\)
\(=x^3\left(x-3\right)-8\left(x-3\right)\)
\(=\left(x-3\right)\left(x-2\right)\left(x^2+2x+4\right)\)
Đúng 0
Bình luận (0)
1: Ta có: \(5x^2y-30xy^2+45y^3\)
\(=5y\left(x^2-6xy+9y^2\right)\)
\(=5y\left(x-3y\right)^2\)
4: Ta có: \(6a^2-ab-2b^2+3a-2b\)
\(=6a^2-4ab+3ab-2b^2+3a-2b\)
\(=\left(3a-2b\right)\left(2a+b+1\right)\)
Đúng 0
Bình luận (0)
Bài 1 phân tích thành nhân tử bằng phương pháp phối hợp nhiều phương pháp
1) 5x^2y - 30xy^2 + 45y^3
2) 3x^3 +3x^2 - 36x
3) x^4 - 4x^3 - 4x^2 +16
4) x^2 (y- z) + y^2 (z - x ) + z^2 ( x- y)
5) 6a^2 -ab - 2b^2 + 3a - 2b
6) x^2 - y^2 - 2x + 2y
7) Xy - 5y + 2x -10
8) 5x^3 - 20x
9) x^3 - 3x^2 - 3x +1
10) 2x^3 + x^2 -8x -4
11) (x^2 + 9)^2 - 36x^2
Bài 1 : Phân tích đa thức thành nhân tử a) 5x^2y-20xy^2b) 1-8x+16x^2-y^2c) 4x-4-x^2d) x^3-2x^2+x-xy^2 e)27-3x^2f) 2x^2+4x+2-2y^2Bài 2: tìm x, biếta) x^2(x-2023)-2023+x0b) -x(x-4)+(2x^3-4x^2-9x):x0c) x^2+2x-3x-60d) 3x(x-10)-2x+200
Đọc tiếp
Bài 1 : Phân tích đa thức thành nhân tử
a) 5x^2y-20xy^2
b) 1-8x+16x^2-y^2
c) 4x-4-x^2
d) x^3-2x^2+x-xy^2
e)27-3x^2
f) 2x^2+4x+2-2y^2
Bài 2: tìm x, biết
a) x^2(x-2023)-2023+x=0
b) -x(x-4)+(2x^3-4x^2-9x):x=0
c) x^2+2x-3x-6=0
d) 3x(x-10)-2x+20=0
Bài 1
a) 5x²y - 20xy²
= 5xy(x - 4y)
b) 1 - 8x + 16x² - y²
= (1 - 8x + 16x²) - y²
= (1 - 4x)² - y²
= (1 - 4x - y)(1 - 4x + y)
c) 4x - 4 - x²
= -(x² - 4x + 4)
= -(x - 2)²
d) x³ - 2x² + x - xy²
= x(x² - 2x + 1 - y²)
= x[(x² - 2x+ 1) - y²]
= x[(x - 1)² - y²]
= x(x - 1 - y)(x - 1 + y)
= x(x - y - 1)(x + y - 1)
e) 27 - 3x²
= 3(9 - x²)
= 3(3 - x)(3 + x)
f) 2x² + 4x + 2 - 2y²
= 2(x² + 2x + 1 - y²)
= 2[(x² + 2x + 1) - y²]
= 2[(x + 1)² - y²]
= 2(x + 1 - y)(x + 1 + y)
= 2(x - y + 1)(x + y + 1)
Đúng 2
Bình luận (1)
Bài 2:
a: \(x^2\left(x-2023\right)+x-2023=0\)
=>\(\left(x-2023\right)\left(x^2+1\right)=0\)
mà \(x^2+1>=1>0\forall x\)
nên x-2023=0
=>x=2023
b:
ĐKXĐ: x<>0
\(-x\left(x-4\right)+\left(2x^3-4x^2-9x\right):x=0\)
=>\(-x\left(x-4\right)+2x^2-4x-9=0\)
=>\(-x^2+4x+2x^2-4x-9=0\)
=>\(x^2-9=0\)
=>(x-3)(x+3)=0
=>\(\left[{}\begin{matrix}x-3=0\\x+3=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-3\end{matrix}\right.\)
c: \(x^2+2x-3x-6=0\)
=>\(\left(x^2+2x\right)-\left(3x+6\right)=0\)
=>\(x\left(x+2\right)-3\left(x+2\right)=0\)
=>(x+2)(x-3)=0
=>\(\left[{}\begin{matrix}x+2=0\\x-3=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-2\end{matrix}\right.\)
d: 3x(x-10)-2x+20=0
=>\(3x\left(x-10\right)-\left(2x-20\right)=0\)
=>\(3x\left(x-10\right)-2\left(x-10\right)=0\)
=>\(\left(x-10\right)\left(3x-2\right)=0\)
=>\(\left[{}\begin{matrix}x-10=0\\3x-2=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{2}{3}\\x=10\end{matrix}\right.\)
Câu 1:
a: \(5x^2y-20xy^2\)
\(=5xy\cdot x-5xy\cdot4y\)
\(=5xy\left(x-4y\right)\)
b: \(1-8x+16x^2-y^2\)
\(=\left(16x^2-8x+1\right)-y^2\)
\(=\left(4x-1\right)^2-y^2\)
\(=\left(4x-1-y\right)\left(4x-1+y\right)\)
c: \(4x-4-x^2\)
\(=-\left(x^2-4x+4\right)\)
\(=-\left(x-2\right)^2\)
d: \(x^3-2x^2+x-xy^2\)
\(=x\left(x^2-2x+1-y^2\right)\)
\(=x\left[\left(x^2-2x+1\right)-y^2\right]\)
\(=x\left[\left(x-1\right)^2-y^2\right]\)
\(=x\left(x-1-y\right)\left(x-1+y\right)\)
e: \(27-3x^2\)
\(=3\left(9-x^2\right)\)
\(=3\left(3-x\right)\left(3+x\right)\)
f: \(2x^2+4x+2-2y^2\)
\(=2\left(x^2+2x+1-y^2\right)\)
\(=2\left[\left(x^2+2x+1\right)-y^2\right]\)
\(=2\left[\left(x+1\right)^2-y^2\right]\)
\(=2\left(x+1+y\right)\left(x+1-y\right)\)
Đúng 1
Bình luận (1)
Bài 2
a) x²(x - 2023) - 2023 + x = 0
x²(x - 2023) - (x - 2023) = 0
(x - 2023)(x² - 1) = 0
x - 2023 = 0 hoặc x² - 1 = 0
*) x - 2023 = 0
x = 2023
*) x² - 1 = 0
x² = 1
x = 1 hoặc x = -1
Vậy x = -1; x = 1; x = 2023
b) -x(x - 4) + (2x³ - 4x² - 9x) : x = 0
-x² + 4x + 2x² - 4x - 9 = 0
x² - 9 = 0
x² = 9
x = 3 hoặc x = -3
Vậy x = 3; x = -3
c) x² + 2x - 3x - 6 = 0
(x² + 2x) - (3x + 6) = 0
x(x + 2) - 3(x + 2) = 0
(x + 2)(x - 3) = 0
x + 2 = 0 hoặc x - 3 = 0
*) x + 2 = 0
x = -2
*) x - 3 = 0
x = 3
Vậy x = -2; x = 3
d) 3x(x - 10) - 2x + 20 = 0
3x(x - 10) - (2x - 20) = 0
3x(x - 10) - 2(x - 10) = 0
(x - 10)(3x - 2) = 0
x - 10 = 0 hoặc 3x - 2 = 0
*) x - 10 = 0
x = 10
*) 3x - 2 = 0
3x = 2
x = 2/3
Vậy x = 2/3; x = 10
Đúng 2
Bình luận (1)
3x^4 + 3x^2y^2 + 6x^3y - 27x^2
x^4 + x^3 - x^2 + x
2x^5 - 6x^4 - 2a^2x^3 - 6ax^3
x^5 + x^4 + x^3 + x^2 + x + 1
x^3 - 1 + 5x^2 - 5 + 3x - 3
1/4.(a + 1)^2 - 4/9.(a - 2)^2
12a^2b^2 - 3.(a^2b^2)^2
4x^2y^2 - (x^2 + y^2 - a^2)^2
(a + b + c)^2 + (a + b - c)^2 - 4c^2
x^3 - 1 + 5x^2 - 5 + 3x - 3
Phân tích đa thức sau thành nhân tử
a) (a^2+b^2)^2-4a^2b^2
b) 3x^2-3xy-5x+5y
c) -x^3+3x^2 -3x+1
d) 2x^2+4xy+2y^2- 8z^2
e) a^3-a^2-a+1
f) x^3-2xy-x^2y+2y^2
e) Ta có: \(a^3-a^2-a+1\)
\(=a^2\left(a-1\right)-\left(a-1\right)\)
\(=\left(a-1\right)\left(a^2-1\right)\)
\(=\left(a-1\right)^2\cdot\left(a+1\right)\)
f) Ta có: \(x^3-2xy-x^2y+2y^2\)
\(=x^2\left(x-y\right)-2y\left(x-y\right)\)
\(=\left(x-y\right)\left(x^2-2y\right)\)
Đúng 3
Bình luận (0)
a) \(\left(a^2+b^2\right)^2-4a^2b^2=\left(a^2+b^2+2ab\right)\left(a^2+b^2-2ab\right)=\left(a+b\right)^2.\left(a-b\right)^2\)
b) \(3x^2-3xy-5x+5y=3x\left(x-y\right)-5\left(x-y\right)=\left(x-y\right)\left(3x-5\right)\)
c) \(-x^3+3x^2-3x+1=\left(1-x\right)^3\)
d) Đề sai ko ???
e) \(a^3-a^2-a+1=a^2\left(a-1\right)-\left(a-1\right)=\left(a-1\right)\left(a^2-1\right)=\left(a-1\right)^2\left(a+1\right)\)
f) \(x^3-2xy-x^2y+2y^2=x^2\left(x-y\right)-2y\left(x-y\right)=\left(x-y\right)\left(x^2-2y\right)\)
Đúng 1
Bình luận (0)
a, \(=\left(a^2+b^2-2ab\right)\left(a^2+b^2+2ab\right)=\left(\left(a-b\right)\left(a+b\right)\right)^2=\left(a^2-b^2\right)^2\)
\(b,=3x\left(x-y\right)-5\left(x-y\right)=\left(x-y\right)\left(3x-5\right)\)
\(c,=-\left(x^2-3x^2+3x-1\right)=-\left(x-1\right)^3\)
\(d,=2\left(x^2+2xy+y^2-4z^2\right)=2\left(\left(x+y\right)^2-4z^2\right)=2\left(x+y-2z\right)\left(x+y+2z\right)\)
\(e,=a^2\left(a-1\right)-\left(a-1\right)=\left(a-1\right)\left(a^2-1\right)\)
\(f,=x^2\left(x-y\right)-2y\left(x-y\right)=\left(x^2-2y\right)\left(x-y\right)\)
Đúng 1
Bình luận (0)
Xem thêm câu trả lời
Phân Tích đa thức thành nhân tử:
a.4xy-10x^2
b.3x(x+1)+6y(x+1)
c.25x^2-y^2
d. 5xy^2-10xyz+5xz^2
e. x^2-5x+6
f. 12x^2y+8x^3+6xy^2+y^3
c: \(=\left(5x-y\right)\left(5x+y\right)\)
e: \(=\left(x-2\right)\left(x-3\right)\)
Đúng 0
Bình luận (0)
a) x(4y-10x)
b)3(x+2y)+(x+1)
c)(5x-y)(5x+y)
d)5x(y-z)2
e)(x-3)(x-2)
f)(2x+y)3
Đúng 0
Bình luận (0)
a) 3x 2 (2x 3 – x + 5)
b) (4xy + 3y – 5x)x 2 y
c) (3x 2 y – 6xy + 9x)(- 3
4
xy)
d) - 3
1
xz(- 9xy + 15yz) + 3x 2 (2yz 2 – yz)
e) (x 3 + 5x 2 – 2x + 1)(x – 7)
f) (2x 2 – 3xy + y 2 )(x + y)
g) (x – 2)(x 2 – 5x + 1) – x(x 2 + 11)
h) [(x 2 – 2xy + 2y 2 )(x + 2y) - (x 2 + 4y 2 )(x – y)] 2xy
Mọi người giúp em với ạ
Đề bài là gì sao không ghi rõ??