Giải pt:
a) 2x3+5x2-3x = 0
b) x3+(x+2) (11x-7) = 4
c) x3+1 = x(x+1)
Cần gấp !
Những câu hỏi liên quan
Tim nghien cua da thuc
a)A(x)=-4x-5 h)K(x)=/3x-2/+/4-6x/
b)B(x)=3(2x-1)-2(x + 1) i)M(x)=/x-1/+(x2-1)2
c)C(x)=(2x2-8)(-x2+1) j)N(x)=4x2-3x+7
d)D(x)=3x-x3 k)Pk(x)=7x2-2x-9
l)Q(x)=5x2-11x+6
e)E(x)=2x3+4x
f)G(x)=x3-x2+x-1
a) Đặt A(x)=0
\(\Leftrightarrow-4x-5=0\)
\(\Leftrightarrow-4x=5\)
hay \(x=-\dfrac{5}{4}\)
b) Đặt B(x)=0
\(\Leftrightarrow3\left(2x-1\right)-2\left(x+1\right)=0\)
\(\Leftrightarrow6x-3-2x-2=0\)
\(\Leftrightarrow4x=5\)
hay \(x=\dfrac{5}{4}\)
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1. (x3 – 3x2 + x – 3) : (x – 3) 2. (2x4 – 5x2 + x3 – 3 – 3x) : (x2 – 3) 3. (x – y – z)5 : (x – y – z)3 4. (x2 + 2x + x2 – 4) : (x + 2) 5. (2x3 + 5x2 – 2x + 3) : (2x2 – x + 1) 6. (2x3 – 5x2 + 6x – 15) : (2x – 5)
1: \(=x^2+1\)
3: \(=\left(x-y-z\right)^2\)
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Cứu với ạ
Làm tính chia
1) (x3 – 3x2 + x – 3) : (x – 3) 2) (2x4 – 5x2 + x3 – 3 – 3x) : (x2 – 3)
3) (x – y – z)5 : (x – y – z)3 4) (x2 + 2x + x2 – 4) : (x + 2)
| 5) (2x3 + 5x2 – 2x + 3) : (2x2 – x + 1) | 6) (2x3 – 5x2 + 6x – 15):(2x – 5) |
3 tháng 5 2022 lúc 19:51
Bài 5: 1) a) Cho hai đa thức: P (x) 5x2 + 3x3 - 5x2 + 2x3 – 2 +4x – 4x2 + x3 Q(x) 6x – x3 + 5 – 4x3 + 6 – 3x2 – 7x2Tính M(x) P(x) + Q(x) b) Tìm C(x) biết: (5x2 + 9x – 3x4 + 7x3 -12) + C(x) -2x3 + 9 – 6x + 7x4 -2x32) Tìm nghiệm của các đa thức sau a) 4x - b) x2 – 4x +3
Đọc tiếp
Bài 5:
1) a) Cho hai đa thức:
P (x) = 5x2 + 3x3 - 5x2 + 2x3 – 2 +4x – 4x2 + x3
Q(x) = 6x – x3 + 5 – 4x3 + 6 – 3x2 – 7x2
Tính M(x) = P(x) + Q(x)
b) Tìm C(x) biết: (5x2 + 9x – 3x4 + 7x3 -12) + C(x) = -2x3 + 9 – 6x + 7x4 -2x3
2) Tìm nghiệm của các đa thức sau
a) 4x - 
b) x2 – 4x +3
a: P(x)=6x^3-4x^2+4x-2
Q(x)=-5x^3-10x^2+6x+11
M(x)=x^3-14x^2+10x+9
b: \(C\left(x\right)=7x^4-4x^3-6x+9+3x^4-7x^3-5x^2-9x+12\)
=10x^4-11x^3-5x^2-15x+21
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7) x4+2x3-2x2+2x-3=0
8) (x-1)( x2+5x-2)-x3+1=0
9) x2+(x+2)(11x-7)=4
(GIẢI PHƯƠNG TRÌNH)
\(x^4+2x^3-2x^2+2x-3=0\\ \Leftrightarrow x^4+3x^3-x^3-3x^2+x^2+3x-x-3=0\\ \Leftrightarrow x^3\left(x+3\right)-x^2\left(x+3\right)+x\left(x+3\right)-\left(x+3\right)=0\\ \Leftrightarrow\left(x+3\right)\left(x^3-x^2+x-1\right)=0\\ \Leftrightarrow\left(x+3\right)\left[x^2\left(x-1\right)+\left(x-1\right)\right]=0\\ \Leftrightarrow\left(x+3\right)\left(x-1\right)\left(x^2+1\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x+3=0\\x-1=0\\x^2+1=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=-3\\x=1\end{matrix}\right.\left(\text{vì }x^2+1\ge1>0\right)\)
Vậy ...
\(\left(x-1\right)\left(x^2+5x-2\right)-x^3+1=0\\ \Leftrightarrow\left(x-1\right)\left(x^2+5x-2\right)-\left(x^3-1\right)=0\\ \Leftrightarrow\left(x-1\right)\left(x^2+5x-2\right)-\left(x-1\right)\left(x^2+x+1\right)=0\\ \Leftrightarrow\left(x-1\right)\left[\left(x^2+5x-2\right)-\left(x^2+x+1\right)\right]=0\\ \Leftrightarrow\left(x-1\right)\left(4x-3\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x-1=0\\4x-3=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=1\\x=\dfrac{3}{4}\end{matrix}\right.\)
Vậy ...
\(x^2+\left(x+2\right)\left(11x-7\right)=4\\ \Leftrightarrow x^2-4+\left(x+2\right)\left(11x-7\right)=0\\ \Leftrightarrow\left(x+2\right)\left(x-2\right)+\left(11x-7\right)=0\\ \Leftrightarrow\left(x+2\right)\left(x-2+11x-7\right)=0\\ \Leftrightarrow\left(x+2\right)\left(12x-9\right)=0\\ \Leftrightarrow3\left(x+2\right)\left(4x-3\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x+2=0\\4x-3=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=-2\\x=\dfrac{3}{4}\end{matrix}\right.\)
Vậy ...
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Bài 1: Thực hiện phép tính:
a) (2x4-x3 5x-6x2-1):(1-2x)
b)(x3-3x2 3x-2):(x2-x 1)
c) (2x3 5x2-2x 3):(2x2-x 1)
d)\(\dfrac{5x y^2}{x^2y}\) \(\dfrac{5y-x^2}{xy^2}\)
e)\(\dfrac{27-x^3}{5x 5}\):\(\dfrac{2x-6}{3x 3}\)
f)\(\dfrac{x 2}{4x 24}\).\(\dfrac...
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27 tháng 4 2023 lúc 23:26
Tính.
a, (x3-2x2-10x-7):(x2-7-3x)
b, (x3+4x2+8x+5):(x+1)
c, (x3-x2-13x-14):(x2-3x-7)
d, (x3+5x2+5x):(x+5)
a: \(=\dfrac{x^3-3x^2-7x+x^2-3x-7}{x^2-3x-7}=x+1\)
b:\(=\dfrac{x^3+x^2+3x^2+3x+5x+5}{x+1}=x^2+3x+5\)
c:\(=\dfrac{x^3-3x^2-7x+2x^2-6x-14}{x^2-3x-7}=x+2\)
d: \(=\dfrac{x^2\left(x+5\right)+5x+25-25}{x+5}=x^2+5-\dfrac{25}{x+5}\)
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Thực hiện phép chia:a) (
2
x
3
+
5
x
2
- 2x + 3) : (2
x
2
- x +1);b) (
x
5
+
x
3
+
x
2
+1) : (
x
3
+1).
Đọc tiếp
Thực hiện phép chia:
a) ( 2 x 3 + 5 x 2 - 2x + 3) : (2 x 2 - x +1);
b) ( x 5 + x 3 + x 2 +1) : ( x 3 +1).
3 tháng 5 2021 lúc 16:45
1) (1-x)(5x+3)=(3x-7)(x-1)
2) (x-2)(x+1)=x2-4
3) 2x3+3x2-32x=48
4) x2+2x-15=0
5) 2x(2x-3)=(3-2x)(2-5x)
6) x3-5x2+6x=0
7) (x2-5)(x+3)=0
8) (x+7)(3x-1)=49-x2
\(\left(1-x\right)\left(5x+3\right)=\left(3x-7\right)\left(x-1\right)\)
\(< =>\left(1-x\right)\left(5x+3+3x-7\right)=0\)
\(< =>\left(1-x\right)\left(8x-4\right)=0\)
\(< =>\orbr{\begin{cases}1-x=0\\8x-4=0\end{cases}< =>\orbr{\begin{cases}x=1\\x=\frac{1}{2}\end{cases}}}\)
\(\left(x-2\right)\left(x+1\right)=x^2-4\)
\(< =>\left(x-2\right)\left(x+1\right)=\left(x-2\right)\left(x+2\right)\)
\(< =>\left(x-2\right)\left(x+1-x-2\right)=0\)
\(< =>-1\left(x-2\right)=0\)
\(< =>2-x=0< =>x=2\)
\(2x^3+3x^2-32x=48\)
\(< =>x^2\left(2x+3\right)-16\left(2x+3\right)=0\)
\(< =>\left(x^2-16\right)\left(2x+3\right)=0\)
\(< =>\left(x-4\right)\left(x+4\right)\left(2x+3\right)=0\)
\(< =>\hept{\begin{cases}x=4\\x=-4\\x=-\frac{3}{2}\end{cases}}\)
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