a) \(x^4-10x^3+25x^2=0\)
\(\Leftrightarrow x^2\left(x^2-10x+25\right)=0\)
\(\Leftrightarrow x^2\left(x-5\right)^2=0\)
\(\Leftrightarrow\left[\begin{array}{nghiempt}x^2=0\\\left(x-5\right)^2=0\end{array}\right.\)\(\Leftrightarrow\left[\begin{array}{nghiempt}x=0\\x=5\end{array}\right.\)
b) \(x^3+3x^2+3x+1=0\)
\(\Leftrightarrow\left(x+1\right)^3=0\)
\(\Leftrightarrow x+1=0\)
\(\Leftrightarrow x=-1\)
a, x4-10x3+25x2=0
<=> x2(x2-10x+25)=0
<=>x2(x-5)2=0
<=>x2=0 hoặc (x-5)2=0
<=>x=0 hoặc x=5
Vậy...
b, x3+3x2+3x+1=0
<=> (x+1)3=0
<=>x+1=0
<=>x=-1 Vậy...
\(a,x^4-10x^3+25x^2=0\)
\(x^2\left(x^2-10x+25\right)=0\)
\(\Leftrightarrow x^2\left(x-5\right)^2=0\)
\(\Leftrightarrow\left[\begin{array}{nghiempt}x^2=0\\\left(x-5\right)^2=0\end{array}\right.\)
\(\Leftrightarrow\left[\begin{array}{nghiempt}x=0\\x=5\end{array}\right.\)
Vậy x=0 hoặc x=5
\(b,x^3+3x^2+3x+1=0\)
\(\Leftrightarrow\left(x+1\right)^3=0\)
\(\Leftrightarrow x+1=0\)
\(\Leftrightarrow x=-1\)
Vậy x=-1
a) \(x^4-10x^3+25x^2=0\)
\(\Rightarrow x^2\left(x^2-10x+25\right)=0\)
\(\Rightarrow x^2\left(x^2-2.5.x+5^2\right)=0\)
\(\Rightarrow x^2\left(x-5\right)^2=0\)
\(\Rightarrow\left[{}\begin{matrix}x^2=0\\\left(x-5\right)^2=0\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}x=0\\x-5=0\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}x=0\\x=5\end{matrix}\right.\)
Vậy \(\left[{}\begin{matrix}x=0\\x=5\end{matrix}\right.\)
b) \(x^3+3x^2+3x+1=0\)
\(\Rightarrow x^3+3x^2.1+3x.1^2+1^3=0\)
\(\Rightarrow\left(x+1\right)^3=0\)
\(\Rightarrow x+1=0\)
\(\Rightarrow x=-1\)
Vậy \(x=-1\)
a)
x4-10x3+25x2=0
=> (x2-5x)=0
=> x(x-5)=0
=> \(\left[\begin{array}{nghiempt}x=0\\x-5=0\end{array}\right.\)
=> \(\left[\begin{array}{nghiempt}x=0\\x=5\end{array}\right.\)
b)
x3+3x2+3x+1=0
=> (x+1)3=0
=> x+1=0
=> x=-1
