1/4 - (2x + 1/2)^2 =0
cíu mình với cần gấp ạ!!!
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
(2x+1)(y+2)=4
⇒(2x+1) và (y+2) ∈ Ư (4) = { 1,-1,2,-2,4,-4 }
⇒2x+1=1 ⇒2x=1-1=0 ⇒x=0:2=0
y+2=4 y=4-2=2 y=2
⇒2x+1=-1 ⇒2x=-1-1=-2 ⇒x=-2:2=-1
y+2=-4 y=-4-2=-6 y=-6
⇒2x+1=2 ⇒2x=2-1=1 ⇒x=1:2=0,5
y+2=-2 y=-2-2=-4 y=-4
\(\left(2x-1\right)\left(y-2\right)=4\)
\(\Rightarrow2x-1\inƯ\left(4\right)=\left\{\pm1;\pm2;\pm4\right\}\)
Mà \(2x+1\) lẻ
\(\Rightarrow2x+1=\pm1\)
Xét \(2x+1=1\Rightarrow x=0\)
\(\Rightarrow y-2=4\Rightarrow y=6\)
Xét \(2x+1=-1\Rightarrow x=-1\)
\(\Rightarrow y-2=-4\Rightarrow y=-2\)
a) \(\left(x+1\right)\left(x+2\right)\left(x+4\right)\left(x+5\right)-4=\left(x^2+6x+5\right)\left(x^2+6x+8\right)-4\)
Đặt \(t=x^2+6x+5\)
\(PT=t\left(t+3\right)-4=t^2+3t-4=\left(t-1\right)\left(t+4\right)\)
Thay t: \(PT=\left(x^2+6x+5-1\right)\left(x^2+6x+5+4\right)=\left(x^2+6x+4\right)\left(x^2+6x+9\right)=\left(x^2+6x+4\right)\left(x+3\right)^2\)
b) Đặt \(t=\left(2x+1\right)^2\)
\(PT=t^2-3t+2=\left(t^2-3t+\dfrac{9}{4}\right)-\dfrac{1}{4}=\left(t+\dfrac{3}{2}\right)^2-\dfrac{1}{4}=\left(t+1\right)\left(t+2\right)\)
Thay t:
\(PT=\left[\left(2x+1\right)^2+1\right]\left[\left(2x+1\right)^2+2\right]=\left[4x^2+4x+2\right]\left[4x^2+4x+3\right]=2\left[2x^2+2x+1\right]\left[4x^2+4x+3\right]\)
\(a,=-15x^3+10x^4+20x^2\\ b,=2x^3+2x^2+4x-x^2-x-2=2x^3+x^2+3x-2\)
\(\left[{}\begin{matrix}\dfrac{1}{2}+2x=0\\2x-3=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x=-\dfrac{1}{2}\\2x=3\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{1}{4}\\x=\dfrac{3}{2}\end{matrix}\right.\)
a) Thay \(x=-1\) và \(y=\dfrac{1}{4}\) vào, ta được:
\(2\cdot\left(-1\right)^2\cdot\dfrac{1}{4}\)
= \(\dfrac{1}{2}\)
b) Thay \(x=-\dfrac{1}{2}\) và \(y=-4\) vào, ta được:
\(-\dfrac{1}{2}\cdot\left(-\dfrac{1}{2}\right)^3\cdot\left(-4\right)^2\)
= \(\left(-\dfrac{1}{2}\right)^4\cdot16\)
= 1
Trả lời
\(\sqrt{x^2+2x+1}+\sqrt{x^2+4x+4}=3\)
\(\Leftrightarrow\sqrt{\left(x+1\right)^2}+\sqrt{\left(x+2\right)^2}=3\)
\(\Leftrightarrow\left|x+1\right|+\left|x+2\right|=3\)
\(\Leftrightarrow x+1+x+2=3\)
\(\Leftrightarrow2x+3=3\)
\(\Leftrightarrow2x=0\)
\(\Leftrightarrow x=0\)
Vậy \(x=0\)
\(\sqrt{x^2+2x+1}+\sqrt{x^2+4x+4}=3\)
\(\Leftrightarrow\sqrt{\left(x+1\right)^2}+\sqrt{\left(x+2\right)^2}=3\)
\(\Leftrightarrow x+1+x+2=3\Leftrightarrow2x+3=3\)
\(\Leftrightarrow2x=0\Leftrightarrow x=0\)
`(x^2-4)(2x+x+3)=0`
`=>(x-2)(x+2)(3x+3)=0`
\(\Rightarrow\left[{}\begin{matrix}x-2=0\\x+2=0\\3x+3=0\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=2\\x=-2\\3x=-3\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=2\\x=-2\\x=-1\end{matrix}\right.\)
Vậy \(x\in\left\{-1;-2;2\right\}\)
\(\left(x^2-4\right)\left(2x+x+3\right)=0\)
=>\(\left(x^2-4\right)\left(3x+3\right)=0\)
=>\(\left(x-2\right)\left(x+2\right)\left(x+1\right)=0\)
=>\(\left[{}\begin{matrix}x-2=0\\x+2=0\\x+1=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=2\\x=-2\\x=-1\end{matrix}\right.\)
Ta có: \(\dfrac{1}{4}-\left(2x+\dfrac{1}{2}\right)^2=0\)
=>\(\left(2x+\dfrac{1}{2}\right)^2=\dfrac{1}{4}\)
=>\(\left[{}\begin{matrix}2x+\dfrac{1}{2}=\dfrac{1}{2}\\2x+\dfrac{1}{2}=-\dfrac{1}{2}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x=0\\2x=-1\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-\dfrac{1}{2}\end{matrix}\right.\)
14−(2x+12)2=014-(2x+12)2=0
⇒(2x+12)2=14−0⇒(2x+12)2=14-0
⇒(2x+12)2=14⇒(2x+12)2=14
⇒(2x+12)2=(12)2⇒(2x+12)2=(12)2 hoặc 2x+12=(−12)22x+12=(-12)2
⇒2x+12=12⇒2x+12=12 hoặc 2x+12=−122x+12=-12
⇒2x=12−12⇒2x=12-12 hoặc 2x=−12−122x=-12-12
⇒2x=0⇒2x=0 hoặc 2x=−12x=-1
⇒x=0:2⇒x=0:2 hoặc x=−1:2x=-1:2
⇒x=0⇒x=0 hoặc x=−12x=-12
Vậy x∈{0;−12}