Tìm x
a) (2x-1)(2x+1)-4(x^2+x)=16
b) 5x(x-2013)-x+2013=0
tìm x,y biết:
a,(x+y)2+(1+x)(1+y)=0
b,(3x-2)(x+1)2(3x+8)=-16
c,(4x-5)(2x-3)(x-1)=9
d,(2x2+x-2013)2+4(x2-5x-2012)2=4(2x2+x-2013)(x2-5x-2012)
I don't now
sorry
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nha
b) \(\left(3x-2\right)\left(x+1\right)^2\left(3x+8\right)=-16\)
\(\Leftrightarrow\)\(\left(3x-2\right)\left(3x+3\right)^2\left(3x+8\right)+144=0\)
Đặt: \(3x+3=a\)pt trở thành:
\(\left(a-5\right)a^2\left(a+5\right)+144=0\)
\(\Leftrightarrow\)\(a^4-25a^2+144=0\)
\(\Leftrightarrow\)\(\left(a-4\right)\left(a-3\right)\left(a+3\right)\left(a+4\right)=0\)
đến đây bạn tìm a rồi tính x
c) \(\left(4x-5\right)\left(2x-3\right)\left(x-1\right)=9\)
\(\Leftrightarrow\)\(\left(4x-5\right)\left(4x-6\right)\left(4x-4\right)-72=0\)
Đặt \(4x-5=a\)pt trở thành:
\(a\left(a-1\right)\left(a+1\right)-72=0\)
\(\Leftrightarrow\)\(a^3-a-72=0\)
p/s: ktra lại đề
d) \(\left(2x^2+x-2013\right)^2+4\left(x^2-5x-2012\right)^2=4\left(2x^2+x-2013\right)\left(x^2-5x-2012\right)\)
\(\Leftrightarrow\)\(\left(2x^2+x-2013\right)^2+4\left(x^2-5x-2012\right)^2-4\left(2x^2+x-2013\right)\left(x^2-5x-2012\right)=0\)
\(\Leftrightarrow\)\(\left[\left(2x^2+x-2013\right)-2\left(x^2-5x-2012\right)\right]^2=0\)
\(\Leftrightarrow\)\(\left(11x+2011\right)^2=0\)
đến đây làm nốt
Tìm x,y biết:
a,(x+y)2+(1+x)(1+y)=0
b,(3x-2)(x+1)2(3x+8)=-16
c,(4x-5)(2x-3)(x-1)=9
d,(2x2+x-2013)2+4(x2-5x-2012)2=4(2x2+x-2013)(x2-5x-2012)
1) Rút gọn biểu thức
A = ( x-3)^2 - (x-5).(x+5)
B = 2.(x+y)(x-y)+(x+y)^2+(x-y)^2
2) Tìm x biết
a) 2x (x+5)-x^2-5x=0
b) 4x (x-2013)-x+2013=0
Bài 1 :
a) \(A=\left(x-3\right)^2-\left(x-5\right)\left(x+5\right)\)
\(A=x^2-6x+9-x^2+25\)
\(A=34-6x\)
b) \(B=2\left(x+y\right)\left(x-y\right)+\left(x+y\right)^2+\left(x-y\right)^2\)
Dễ thấy đây là HĐT thứ 1
\(B=\left(x+y+x-y\right)^2\)
\(B=\left(2x\right)^2\)
\(B=4x^2\)
Bài 2 :
a) \(2x\left(x+5\right)-x^2-5x=0\)
\(2x\left(x+5\right)-x\left(x+5\right)=0\)
\(\left(x+5\right)\left(2x-2\right)=0\)
\(2\left(x+5\right)\left(x-1\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x+5=0\\x-1=0\end{cases}\Rightarrow\orbr{\begin{cases}x=-5\\x=1\end{cases}}}\)
b) \(4x\left(x-2013\right)-x+2013=0\)
\(4x\left(x-2013\right)-\left(x-2013\right)=0\)
\(\left(x-2013\right)\left(4x-1\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x-2013=0\\4x-1=0\end{cases}\Rightarrow\orbr{\begin{cases}x=2013\\x=\frac{1}{4}\end{cases}}}\)
a) 2x-1/11+2x-2/12+2x-3/13=2x+5/5+2x+6/4+2x+7/3
b) x-1/2016+x-2/2015+x-3/2014+x-4/2013+x-5/2012 -5=0
c) x+2017/2+x+2015/3+x+2013/4+x+2011/5+8=0
1. Tìm x biết:
a,5x.( x+3/4)=0
b, x+7/ 2010+ x+6/2011 =x+5 / 2012 + x + 4 /2013
2. Tìm x sao cho:
a, 2x-3 có giá trị dương
b, 13-5x có giá trị âm
c, x+3/2x-1 > 0
d, x+7/x+3 < 1
Giúp mk vs nha mk đang cần gấp. Mk tick cho. Thank nhìu
a) 5x.(x+3/4) = 0
=> x = 0
x+3/4 = 0 => x = -3/4
b) \(\frac{x+7}{2010}+\frac{x+6}{2011}=\frac{x+5}{2012}+\frac{x+4}{2013}.\)
\(\Rightarrow\frac{x+7}{2010}+\frac{x+6}{2011}-\frac{x+5}{2012}-\frac{x+4}{2013}=0\)
\(\frac{x+7}{2010}+1+\frac{x+6}{2011}+1-\frac{x+5}{2012}-1-\frac{x+4}{2013}-1=0\)
\(\left(\frac{x+7}{2010}+1\right)+\left(\frac{x+6}{2011}+1\right)-\left(\frac{x+5}{2012}+1\right)-\left(\frac{x+4}{2013}+1\right)=0\)
\(\frac{x+2017}{2010}+\frac{x+2017}{2011}-\frac{x+2017}{2012}-\frac{x+2017}{2013}=0\)
\(\left(x+2017\right).\left(\frac{1}{2010}+\frac{1}{2011}-\frac{1}{2012}-\frac{1}{2013}\right)=0\)
=> x + 2017 = 0
x = -2017
a) để 2x - 3 > 0
=> 2x > 3
x > 3/2
b) 13-5x < 0
=> 5x < 13
x < 13/5
c) \(\frac{x+3}{2x-1}>0\)
=> x + 3 > 0
x > -3
d) \(\frac{x+7}{x+3}=\frac{x+3+4}{x+3}=1+\frac{4}{x+3}\)
Để x+7/x+3 < 1
=> 1 + 4/x+3 < 1
=> 4/x+3 < 0
=> không tìm được x thỏa mãn điều kiện
Giải pt
(2x^2+x-2013)^2+4(x^2-5x-2012)^2=4(2x^2+x-2013)(x^2-5x-2012
a) 2x-1/11+2x-2/12+2x-3/13=2x+5/5+2x+6/4+2x+7/3
b) x-1/2016+x-2/2015+x-3/2014+x-4/2013+x-5/2012 -5=0
c) x+2017/2+x+2015/3+x+2013/4+x+2011/5+8=0
giúp mình với mọi người làm ơn đi mình cần gấp lắm!!!!
a) 2x-1/11+2x-2/12+2x-3/13=2x+5/5+2x+6/4+2x+7/3
b) x-1/2016+x-2/2015+x-3/2014+x-4/2013+x-5/2012 -5=0
c) x+2017/2+x+2015/3+x+2013/4+x+2011/5+8=0
giúp mình với mọi người làm ơn đi mình cần gấp lắm!!!!
Tìm x
a. 5x (x-2013)-2x+4026=0
b.x^2(x+5)-9(x+5)=0
(x^2= x mũ 2 nhé)