Tim nghiem
x^3 +2x^2+2x+1
C(x)=-2x(2x-3)-2(x-1)
Q(x)=2(x-3)-(x-1)
Tim nghiem
Đặt C(x)=0
\(\Leftrightarrow-2x\left(2x-3\right)-2\left(x-1\right)=0\)
\(\Leftrightarrow-4x^2+6x-2x+2=0\)
\(\Leftrightarrow-4x^2+4x+2=0\)
\(\Leftrightarrow4x^2-4x-2=0\)
\(\Leftrightarrow\left(2x-1\right)^2=3\)
\(\Leftrightarrow\left[{}\begin{matrix}2x-1=\sqrt{3}\\2x-1=-\sqrt{3}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x=\sqrt{3}+1\\2x=-\sqrt{3}+1\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{\sqrt{3}+1}{2}\\x=\dfrac{-\sqrt{3}+1}{2}\end{matrix}\right.\)
Đặt Q(x)=0
\(\Leftrightarrow2\left(x-3\right)-\left(x-1\right)=0\)
\(\Leftrightarrow2x-6-x+1=0\)
\(\Leftrightarrow x=5\)
Tim nghiem
a) 2x-3
b)x^3+1
c) x^2-2x+1
a) \(2x-3=0\Leftrightarrow x=\frac{3}{2}\)
b) \(x^3+1=0\)
\(\Leftrightarrow x^3=-1\)
\(\Leftrightarrow x^3=\left(-1\right)^3\Leftrightarrow x=-1\)
c) \(x^2-2x+1=0\)
\(\Leftrightarrow\left(x-1\right)^2=0\)
\(\Leftrightarrow x-1=0\)
\(\Leftrightarrow x=1\)
a) \(2x-3=0\)
\(\Leftrightarrow2x=0+3\)
\(\Leftrightarrow2x=3\)
\(\Leftrightarrow x=3\div2\)
\(\Leftrightarrow x=1,5\)
Vậy nghiệm của đa thức 2x - 3 là 1,5.
b. \(x^3+1=0\)
\(\Leftrightarrow x^3=0-1\)
\(\Leftrightarrow x^3=-1\)
\(\Leftrightarrow x^3=-1^3\)
\(\Leftrightarrow x=-1\)
Vậy nghiệm của đa thức x3 + 1 là - 1.
c) \(x^2-2x+1=0\)
\(\Leftrightarrow x^2-2x=0-1\)
\(\Leftrightarrow x\left(x-2\right)=-1=-1.1=1.\left(-1\right)\)
Vậy đa thức \(x^2-2x+1\) vô nghiệm
Trả lời.............
a,2x-3=0
2x=0-3
2x=3
x=3:2
x=3/2
b,x3+1=0
X3=-13
X=-1
c,X2-2x+1
X=1
..........................học tốt..........................
Tim nghiem:
a,3(1-x)-5(2x-2)
b, gia tri tuyet doi 3x-2 -4
c, 2x-x^3
d, x(1-2x)+(2x^2-x+4)
a/ 3(1 - x) - 5(2x - 2) = 0
=> 3 - 3x - 10x + 10 = 0
=> -13x = -13
=> x = 1
Vậy x = 1
b/ |3x - 2| - 4 = 0 => |3x - 2| = 4
Suy ra 2 trường hợp:
3x - 2 = 4 => 3x = 6 => x = 2 3x - 2 = -4 => 3x = -2 => x = -2/3Vậy x = 2 , x = -2/3
c/ 2x - x3 = 0 => x.(2 - x2) = 0
=> x = 0
hoặc 2 - x2 = 0 => x2 = 2 => x = \(\sqrt{2}\) hoặc x = \(-\sqrt{2}\)
Vậy \(x=\left\{0;\sqrt{2};-\sqrt{2}\right\}\)
d/ x(1 - 2x) + (2x2 - x + 4) = 0
=> x - 2x2 + 2x2 - x + 4 = 0
=> 4 = 0 (vô lí)
Vậy vô nghiệm
Tim m de pt \(x^2-2x-2\left|x-m\right|+1=0\) co 3 nghiem phan biet
tim nghiem nguyen cua phuong trinh: \(\left(x^2+1\right)\sqrt{1-x}-\left(2x+x^3\right)\sqrt{x+1}=3x^4\sqrt{2x}\)
Tim nghiem
c.)C(x)=\(\dfrac{1}{2}-7x+2x^3-2.\left(x+2^3+x^3\right)\)
đặt C(x)=0
\(\Leftrightarrow-7x+\dfrac{1}{2}+2x^3-2x-16-2x^3=0\)
=>-9x-31/2=0
=>-9x=31/2
hay x=-31/18
tim da thuc f(x) roi tim nghiem cua f(x) biet rang:x^3+2x^2(4y-1)-4xy^2-9y^3-f(x)=-5x^3+8x^2y-4xy^2-9y^3
Tim nghiem cua da thuc :
a,3x^2+5x+2
b,x(3-2x)x-(-2x^2+5x-4)
c,x^3+3x
Tim nghiem da thuc:(2x-5).(x2+1)