\(^{\left(2x-3\right)^5=\left(2x-3\right)^{2020}}\)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(y=\dfrac{1}{2x^2+x-1}=\dfrac{1}{\left(x+1\right)\left(2x-1\right)}=\dfrac{2}{3}.\dfrac{1}{2x-1}-\dfrac{1}{3}.\dfrac{1}{x+1}\)
\(y'=\dfrac{2}{3}.\dfrac{-2}{\left(2x-1\right)^2}-\dfrac{1}{3}.\dfrac{-1}{\left(x+1\right)^2}=\dfrac{2}{3}.\dfrac{\left(-1\right)^1.2^1.1!}{\left(2x-1\right)^2}-\dfrac{1}{3}.\dfrac{\left(-1\right)^1.1!}{\left(x+1\right)^2}\)
\(y''=\dfrac{2}{3}.\dfrac{\left(-1\right)^2.2^2.2!}{\left(2x-1\right)^3}-\dfrac{1}{3}.\dfrac{\left(-1\right)^2.2!}{\left(x+1\right)^3}\)
\(\Rightarrow y^{\left(n\right)}=\dfrac{2}{3}.\dfrac{\left(-1\right)^n.2^n.n!}{\left(2x-1\right)^{n+1}}-\dfrac{1}{3}.\dfrac{\left(-1\right)^n.n!}{\left(x+1\right)^{n+1}}\)
\(\Rightarrow y^{\left(2019\right)}=\dfrac{2}{3}.\dfrac{\left(-1\right)^{2019}.2^{2019}.2019!}{\left(2x-1\right)^{2020}}-\dfrac{1}{3}.\dfrac{\left(-1\right)^{2019}.2019!}{\left(x+1\right)^{2020}}\)
\(=\dfrac{2019!}{3}\left(\dfrac{1}{\left(x+1\right)^{2020}}-\dfrac{2^{2020}}{\left(2x-1\right)^{2020}}\right)\)
![](https://rs.olm.vn/images/avt/0.png?1311)
câu c mình không chắc là do đề hay là do mình chưa từng gặp dạng này
![](https://rs.olm.vn/images/avt/0.png?1311)
1: \(\Leftrightarrow2x^2-10x-3x-2x^2=0\)
=>-13x=0
=>x=0
2: \(\Leftrightarrow5x-2x^2+2x^2-2x=13\)
=>3x=13
=>x=13/3
3: \(\Leftrightarrow4x^4-6x^3-4x^3+6x^3-2x^2=0\)
=>-2x^2=0
=>x=0
4: \(\Leftrightarrow5x^2-5x-5x^2+7x-10x+14=6\)
=>-8x=6-14=-8
=>x=1
`1)2x(x-5)-(3x+2x^2)=0`
`<=>2x^2-10x-3x-2x^2=0`
`<=>-13x=0`
`<=>x=0`
___________________________________________________
`2)x(5-2x)+2x(x-1)=13`
`<=>5x-2x^2+2x^2-2x=13`
`<=>3x=13<=>x=13/3`
___________________________________________________
`3)2x^3(2x-3)-x^2(4x^2-6x+2)=0`
`<=>4x^4-6x^3-4x^4+6x^3-2x^2=0`
`<=>x=0`
___________________________________________________
`4)5x(x-1)-(x+2)(5x-7)=0`
`<=>5x^2-5x-5x^2+7x-10x+14=0`
`<=>-8x=-14`
`<=>x=7/4`
___________________________________________________
`5)6x^2-(2x-3)(3x+2)=1`
`<=>6x^2-6x^2-4x+9x+6=1`
`<=>5x=-5<=>x=-1`
___________________________________________________
`6)2x(1-x)+5=9-2x^2`
`<=>2x-2x^2+5=9-2x^2`
`<=>2x=4<=>x=2`
![](https://rs.olm.vn/images/avt/0.png?1311)
a: ĐKXĐ: \(x\notin\left\{\dfrac{5}{2}\right\}\)
\(\log_32x-5=3\)
=>\(log_3\left(2x-5\right)=log_327\)
=>2x-5=27
=>2x=32
=>x=16(nhận)
b: ĐKXĐ: x<>0
\(\log_4x^2=2\)
=>\(log_4x^2=log_416\)
=>\(x^2=16\)
=>\(\left[{}\begin{matrix}x=4\left(nhận\right)\\x=-4\left(nhận\right)\end{matrix}\right.\)
c: ĐKXĐ: \(x\notin\left\{\dfrac{1}{3};-\dfrac{5}{2}\right\}\)
\(\log_7\left(3x-1\right)=\log_7\left(2x+5\right)\)
=>3x-1=2x+5
=>x=6(nhận)
d: ĐKXĐ: \(x\notin\left\{1;-1;\dfrac{-1+\sqrt{13}}{4};\dfrac{-1-\sqrt{13}}{4}\right\}\)
\(ln\left(4x^2+2x-3\right)=ln\left(3x^2-3\right)\)
=>\(4x^2+2x-3=3x^2-3\)
=>\(x^2+2x=0\)
=>x(x+2)=0
=>\(\left[{}\begin{matrix}x=0\\x+2=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\left(nhận\right)\\x=-2\left(nhận\right)\end{matrix}\right.\)
e: ĐKXĐ: \(x\notin\left\{-\dfrac{3}{2};\dfrac{1}{3}\right\}\)
\(log\left(2x+3\right)=log\left(1-3x\right)\)
=>2x+3=1-3x
=>5x=-2
=>\(x=-\dfrac{2}{5}\left(nhận\right)\)
\(\left(2x-3\right)^5=\left(2x-3\right)^{2020}\)
\(\Leftrightarrow\left(2x-3\right)^{2020}-\left(2x-3\right)^5=0\)
\(\Leftrightarrow\left(2x-3\right)^5\left[\left(2x-3\right)^{2015}-1\right]=0\)
\(\Leftrightarrow\orbr{\begin{cases}\left(2x-3\right)^5=0\\\left(2x-3\right)^{2015}-1=0\end{cases}\Leftrightarrow\orbr{\begin{cases}2x-3=0\\\left(2x-3\right)^{2015}=1\end{cases}}}\)
\(\Leftrightarrow\orbr{\begin{cases}2x=3\\2x-3=1\end{cases}\Leftrightarrow\orbr{\begin{cases}x=\frac{3}{2}\\x=2\end{cases}}}\)
Vậy\(x=\frac{3}{2};2\)
Vì ( 2x - 3 )5 = ( 2x - 3 )2020
\(\Rightarrow\orbr{\begin{cases}2x-3=1\\2x-3=0\end{cases}\Rightarrow\orbr{\begin{cases}2x=1+3\\2x=0+3\end{cases}\Rightarrow}\orbr{\begin{cases}2x=4\\2x=3\end{cases}\Rightarrow}\orbr{\begin{cases}x=4:2\\x=3:2\end{cases}\Rightarrow}\orbr{\begin{cases}x=2\\x=\frac{3}{2}\end{cases}}}\)
Vậy \(x\in\left\{2;\frac{3}{2}\right\}\)thì ( 2x - 3 )5 = ( 2x - 3 )2020