gpt (x+1)/(x^2+x+1) -(x-1)/(x^2-x+1)=(5-3x)/(x^6+x^4+x^2)
Những câu hỏi liên quan
gpt : a. \(x^2-7x=6\sqrt{x+5}-30\)
b. \(\sqrt{3x^2-5x+1}-\sqrt{x^2-2}=\sqrt{3\left(x^2-x-1\right)}-\sqrt{x^2-3x-4}\)
a) Điều kiện $x \ge -5$. Đặt $\sqrt{x+5}=a$ thì $x=a^2-5$. Thay vào ta có $$\begin{array}{l} (a^2-5)^2-7(a^2-5)=6a-30 \\ \Leftrightarrow a^4-17a^2-6a+90=0 \Leftrightarrow (a^2+6a+10)(a-3)^2=0 \end{array}$$
Vậy $a=3 \Leftrightarrow \boxed{ x= 4}$.
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gpt: \(\frac{1}{x^2-3x+3}+\frac{2}{x^2-3x+4}=\frac{6}{x^2-3x+5}\)
Đặt x2-3x+4=a
=>\(\frac{1}{a-1}+\frac{2}{a}=\frac{6}{a+1}\)
ĐKXĐ:a khác 1 ; -1 ;0
=>a2+a+2a2-2=6a2-6a
<=>6a2-3a2-a-6a+2=0
<=>3a2-7a+2=0
<=>(3a-1)(a-2)=0
<=>a=1/3 hoặc a=2
*)a=1/3
=>x2-3x+4=1/3
<=>x2-3x+11/3=0
<=>(x-1,5)2+17/12=0(vô lí)
*)a=2
=>x2-3x+4=2
<=>x2-3x+2=0
<=>(x-1)(x-2)=0
<=>x=1 hoặc x=2
Vậy x={1;2}
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GPT:
(3x+4)^2-(3x-1).(3x+1)=49
(x+2).(x^2-2x+4)-x.(x+3).(x-3)
(3x+4)2-(3x-1).(3x+1)=49
<=> 9x2+24x+16-(9x2-1)=49
<=>9x2+24x+16-9x2+1=49
<=>24x+17=49
<=>24x =32
<=>x =4/3
Vậy ...
(x+2).(x^2-2x+4)-x.(x+3).(x-3)
=x3+8-x(x2-9)
=x3+8-x3+9x
=9x+8
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(3x+4)2-(3x-1).(3x+1)=49
<=> 9x2+24x+16-(9x2-1)=49
<=>9x2+24x+16-9x2+1=49
<=>24x+17=49
<=>24x =32
<=>x =4/3
Vậy ...
(x+2).(x^2-2x+4)-x.(x+3).(x-3)
=x3+8-x(x2-9)
=x3+8-x3+9x
=9x+8
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gpt: \(2\sqrt{3x+7}-5\sqrt[3]{x-6}=4\)
\(\left(x^2-3x+2\right)\left(x^2-12x+32\right)\le4x^2\)
\(\left(\sqrt{x+1}-1\right)\left(\sqrt{x^2-4x+7}+1\right)=x\)
GPT: \(x^3+x^2+1=\left(x^3-3x+2\right).2018^{x^2+3x-1}+\left(x^2+3x-1\right).2018^{x^3-3x+2}\)
gpt : \(x^2-4x+5-\frac{3x}{x^2+x+1}=\left(x-1\right)\left(1-\frac{2\sqrt{1-x}}{\sqrt{x^2+x+1}}\right)\)
a, Gpt
x^4 -2x^3+4x^2-3x=4
b, /x+1/+/x-1/=1+/x^2-1/
12 tháng 12 2021 lúc 9:56
Gpt: \(5\sqrt{x-1}-\sqrt{x+7}=3x-4\) (2 cách)
Cách 1:
GPT :\(5\sqrt{x-1}-\sqrt{x+7}=3x-4\) - Hoc24
Cách 2:
Đặt \(\left\{{}\begin{matrix}\sqrt{25x-25}=a\\\sqrt{x+7}=b\end{matrix}\right.\) \(\Rightarrow3x-4=\dfrac{a^2-b^2}{8}\)
Pt trở thành:
\(a-b=\dfrac{a^2-b^2}{8}\)
\(\Leftrightarrow\left(a-b\right)\left(a+b-8\right)=0\)
\(\Leftrightarrow...\)
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1 tháng 12 2018 lúc 14:12
Tìm x biết:
1. (x-2)^2-(x-3)(x+3)=6
2. 4(x-3)^2-(2x-1)(2x+1)=10
3. (x-4)^2-(x-2)(x+2)=6
4.9(x+1)^2-(3x-2)(3x+2)=10
5. 3x +2(5-x)=0
6.x(2x-1)(x+5)-(2x^2+1)(x+4,5)=3,5
7, 3x^2-3x(x-2)=36
8. (3x^2-x+1)(x-1) +x^2(4-3x)=5/2
