Tìm x biết: a)x+2/3-x>0
b)x+2/3-x
Bài 13: Tìm x biết: a) (x-2)(x-3)-D0. b) (x-3)(x-4)-0. c) (x-7)(6-x)=0. d) (x-3)(x-13)=0. The Bài 14: Tìm x biết: a) (12-x)(2-x)=0. b) (x-33)(11-x)=0. c) (21-x)(12-x)=0. d) (50-x)(x-150) =0. Bài 15: Tìm x biết: a) 2x +x = 45. b) 2x +7x = 918. c) 2x+3x 60+5. d) 11x+22x 33.2.
Tìm x biết:
a) x 2 + 3 x = 0 b) x ( 2x − 1) + 4x − 2=0 c) ( x 2 + 2 x )2 − 2 x 2 − 4 x = 3
a. x( x+ 3)= 0
⇔ x= 0 hoặc x+ 3= 0
⇔ x= 0 x = -3
b. x( 2x− 1)+ 2( 2x− 1) =0
⇔ ( 2x− 1)(x+ 2) =0
⇔ 2x− 1 =0 hoặc x+ 2 =0
⇔ 2x =1 x = -2
⇔ x =\(\dfrac{1}{2}\) x = -2
tìm x biết : a)x(x-3)-x^2+5=0 b)x^2-6x=0 c)2x^3+5x^2-012x=0
a: Ta có: \(x\left(x-3\right)-x^2+5=0\)
\(\Leftrightarrow-3x+5=0\)
hay \(x=\dfrac{5}{3}\)
b: Ta có: \(x^2-6x=0\)
\(\Leftrightarrow x\left(x-6\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=6\end{matrix}\right.\)
\(a,\left(x+2\right)^{10}+\left(x+2\right)^8=0\\ \Leftrightarrow\left(x+2\right)^8\left[\left(x+2\right)^2+1\right]=0\\ \Leftrightarrow\left[{}\begin{matrix}\left(x+2\right)^8=0\\\left(x+2\right)^2+1=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x+2=0\\\left(x+2\right)^2=-1\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=-2\\x\in\varnothing\end{matrix}\right.\\ b,\left(x+3\right)^{10}-\left(x+3\right)^8=0\\ \Leftrightarrow\left(x+3\right)^8\left[\left(x+3\right)^2-1\right]=0\\ \Leftrightarrow\left[{}\begin{matrix}\left(x+3\right)^8=0\\\left(x+3\right)^2-1=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x+3=0\\\left(x+3\right)^2=1\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=-3\\x+3=1\\x+3=-1\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-3\\x=-2\\x=-4\end{matrix}\right.\)
Tìm x biết: a)x(x-3)+x-3=0 b)(5x-4)^2-16^2=0
1, Tìm x, biết
a, | x + 1 | + | x + 2| + | x + 3 | = x
b, | x - 3 | + | x - 1 | =3
2, Cho M = x + 2 \ x - 3
a, Tìm x để M = 0
b, Tìm x để M < 0
c, Tìm x để M > 0
Tìm x, biết:
a) x(x - 2) + x - 2 = 0;
b) 5x(x - 3) - x + 3 = 0
a. x(x-2)+x-2=0
=> (x-2).(x+1)=0
=> x-2=0 hoặc x+1=0
=> x=2 hoặc x=-1
b. 5x(x-3)-x+3=0
=> 5x(x-3)-(x-3)=0
=> (x-3).(5x-1)=0
=> x-3=0 hoặc 5x-1=0
=> x=3 hoặc x=1/5
a) x(x - 2) + x - 2 = 0;
<=>x.(x-2)+(x-2)=0
<=>(x-2)(x+1)=0
<=>x-2=0 hoặc x+1=0
<=>x=2 hoặc x=-1
b) 5x(x - 3) - x + 3 = 0
<=>5x.(x-3)-(x-3)=0
<=>(x-3)(5x-1)=0
<=>x-3=0 hoặc 5x-1=0
<=>x=3 hoặc x=1/5
tìm x biết
a,(x-2).(3-x)>0
b,(x-2).(3-x)<0
\(\left(x-2\right)\left(3-x\right)>0\)
\(\Leftrightarrow\hept{\begin{cases}x-2>0\\3-x>0\end{cases}}\)hoặc \(\hept{\begin{cases}x-2< 0\\3-x< 0\end{cases}}\)
\(\Leftrightarrow\hept{\begin{cases}x>2\\x< 3\end{cases}}\)hoặc \(\hept{\begin{cases}x< 2\\x>3\end{cases}\left(loai\right)}\)
\(\Leftrightarrow2< x< 3\)
Vậy\(2< x< 3\)
\(\left(x-2\right)\left(3-x\right)< 0\)
\(\Leftrightarrow\hept{\begin{cases}x-2< 0\\3-x>0\end{cases}}\)hoặc \(\hept{\begin{cases}x-2>0\\3-x< 0\end{cases}}\)
\(\Leftrightarrow\hept{\begin{cases}x< 2\\x>3\end{cases}\left(loai\right)}\)hoặc \(\hept{\begin{cases}x>2\\x< 3\end{cases}}\)
\(\Leftrightarrow2< x< 3\)
Vậy \(2< x< 3\)
Tìm x, biết : a.,(x-y)^2-(x-3).(x+3)=6; b, x^2-5x=0;c,x^2+6x+5=0
Tìm x,biết
A) x(x-2)+x-2=0
B) 5x(x-3)-x+3=0
x(x-2) + x-2= x(x-2) + (x-2).1=(x-2)(x+1)
à như thế này
x (x-2) + 1( x - 2) = 0
(x - 2)( x + 1) = 0