Ai giúp mik làm bài này với . Mik cảm ơn
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My taste in art is not the same as my sister's
I think romantic films aren't as interesting as action films
I don't speak Japanese and my new friend doesn't, either
Nester goes climbing less than before
He's had a cold for 2 days because he didn't wear enough clothes
I will spend an hour gettign this task done
My father prefers tea to coffee
Eat less or you will be obese
a) Ta có: \(\left(2x+7\right)^2=\left(x+3\right)^2\)
\(\Leftrightarrow\left(2x+7\right)^2-\left(x+3\right)^2=0\)
\(\Leftrightarrow\left(2x+7-x-3\right)\left(2x+7+x+3\right)=0\)
\(\Leftrightarrow\left(x+4\right)\cdot\left(3x+10\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x+4=0\\3x+10=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-4\\3x=-10\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-4\\x=-\dfrac{10}{3}\end{matrix}\right.\)
Vậy: \(S=\left\{-4;-\dfrac{10}{3}\right\}\)
b) Ta có: \(\left(4x+14\right)^2=\left(7x+2\right)^2\)
\(\Leftrightarrow\left(4x+14\right)^2-\left(7x+2\right)^2=0\)
\(\Leftrightarrow\left(4x+14-7x-2\right)\left(4x+14+7x+2\right)=0\)
\(\Leftrightarrow\left(-3x+12\right)\left(11x+16\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}-3x+12=0\\11x+16=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}-3x=-12\\11x=-16\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=4\\x=-\dfrac{16}{11}\end{matrix}\right.\)Vậy: \(S=\left\{4;-\dfrac{16}{11}\right\}\)
(2x+7)2=(x+3)2
=>(2x+7)2-(x+3)2=0
=>(2x+7-x-3)(2x+7+x+3)=0
=>(x-4)(3x+10)=0
=>x-4=0 hoặc 3x+10=0
TH1:x-4=0=>x=4
TH2:3x+10=0=>x=-10/3
(4x+14)2=(7x+2)2
(4x+14)2-(7x+2)2=0
(4x+14-7x-2)(4x+14+7x+2)=0
(-3x+12)(11x+16)=0
TH1:-3x+12=0=>x=4
TH2:11x+16=0=>x=-16/11
1: =>x^2-5x+6-x^2-5x-6=x^2+1-x^2+9
=>-10x=10
=>x=-1(nhận)
2: \(\Leftrightarrow3x^2-15x-x^2+2x-2x^2=0\)
=>-13x=0
=>x=0
3: \(\Leftrightarrow13\left(x+3\right)+x^2-9=12x+42\)
=>x^2-9+13x+39-12x-42=0
=>x^2+x-12=0
=>(x+4)(x-3)=0
=>x=3(loại) hoặc x=-4(nhận)
4: \(\Leftrightarrow-2+x^2-5x+4=x^2+x-6\)
=>-5x-2=x-6
=>-6x=-4
=>x=2/3