\(\left(x-7\right)^{x+1}-\left(x-7\right)^{x+11}=0\)0
\(\left(X-7\right)^{x+1}-\left(x-7\right)^{x+11}=0\) \(\)
\(\Rightarrow\left(x-7\right)^{x+1}\left[1-\left(x-7\right)^{10}\right]=0\\ \Rightarrow\left[{}\begin{matrix}\left(x-7\right)^{x+1}=0\\1-\left(x-7\right)^{10}=0\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x-7=0\\\left(x-7\right)^{10}=1\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=7\\x=8\end{matrix}\right.\)
Tìm x
\(\left(x-7\right)^{x+1}-\left(x-7\right)^{x+11}=0\)
\(\Leftrightarrow\left(x-7\right)\left(x-6\right)\left(x-8\right)=0\)
hay \(x\in\left\{6;7;8\right\}\)
\(\Leftrightarrow\left(x-7\right)^{x+1}-\left(x-7\right)^{x+1}\left(x-7\right)^{10}=0\)
\(\Leftrightarrow\left(x-7\right)^{x+1}.\left(1-\left(x-7\right)^{10}\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-7=0\\\left(x-7\right)^{10}=1\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=7\\\left[{}\begin{matrix}x-7=1\Rightarrow x=8\\x-7=-1\Rightarrow x=6\end{matrix}\right.\end{matrix}\right.\)
Vậy \(x=\left\{6;7;8\right\}\)
tìm xϵZ biết:
\(\left(x-7\right)^{x+1}-\left(x-7\right)^{x+11}=0\)
\(\Leftrightarrow\left(x-7\right)^{x+1}\left[1-\left(x-7\right)^{10}\right]=0\\ \Leftrightarrow\left[{}\begin{matrix}\left(x-7\right)^{x+1}=0\\\left(x-7\right)^{10}=1\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x-7=0\\x-7=1\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=7\\x=8\end{matrix}\right.\)
Tìm x biết
a,\(\left|x-\dfrac{1}{3}\right|+\dfrac{4}{5}=\left|\left(-3,2\right)+\dfrac{2}{5}\right|b,\left(x-7\right)^{x+1}+\left(x-7\right)^{x+11}=0\)
\(\left(x-7\right)^{x+1}-\left(x-7\right)^{x+11}=0\)
\(\left(x-7\right)^{x+1}-\left(x-7\right)^{x+11}=0\)
\(\Rightarrow\left(x-7\right)^{x+1}\left[1-\left(x-7\right)^{10}\right]=0\)
\(\Rightarrow\left(x-7\right)^{x+1}\left[1^2-\left(x-7\right)^{5^2}\right]=0\)
\(\Rightarrow\left(x-7\right)^{x+1}\left[1-\left(x-7\right)^5\right]\left[1+\left(x-7\right)^5\right]=0\)
=>(x-7)x+1=0 hoặc 1-(x-7)5=0 hoặc 1+(x-7)5=0
+)Nếu (x-7)x+1=0
=>x-7=0
=>x=7
+)Nếu 1-(x-7)5=0
=>(x-7)5=1
=>x-7=1
=>x=8
+)Nếu 1+(x-7)5=0
=>(x-7)5=-1
Vì \(\left(x-7\right)^5\ge0\) với mọi x
=>không tìm được x thỏa mãn 1+(x-7)5=0
Vậy x=7 hoặc x=8
Tìm x biết :\(\left(x-7\right)^{x+1}-\left(x-7\right)^{x+11}=0\)\(0\)
\(\left|x-\frac{1}{3}\right|+\frac{4}{5}=\left|\left(-3,2\right)+\frac{2}{5}\right|\)
\(\left(x-7\right)^{x+1}-\left(x-7\right)^{x+11}=0\)
\(\left|x-\frac{1}{3}\right|+\frac{4}{5}=\left|\frac{-14}{5}\right|\)
\(\left|x-\frac{1}{3}\right|=2\)
\(\Rightarrow\orbr{\begin{cases}x-\frac{1}{3}=2\\x-\frac{1}{3}=-2\end{cases}\Rightarrow\orbr{\begin{cases}x=\frac{7}{3}\\-\frac{5}{3}\end{cases}}}\)
Vậy...
\(\Rightarrow\left(x-7\right)^{x+1}.\left(1-\left(x-7\right)^{10}\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x-7=0\\\left(x-7\right)^{10}=1=1^{10}\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=7\\x=6;x=8\end{cases}}\)
Tìm x biết \(\left(x-7\right)^{x+1}-\left(x-7\right)^{x+11}=0\)
=> (x-7)^x+1 + 1.[1-(x-7)^10] = 0
=> x-7 = 0 hoặc 1-(x-7)^10 = 0
=> x=7 hoặc x = 8 hoặc x = 6
k mk nha
A)\(^{ }\left(^{ }x+1\right)\left(2x-1\right)\left(-x+2\right)=0\)
B)\(^{ }\left(2x-1\right)\left(3x+2\right)\left(4x-5\right)\left(x-7\right)=0\)
C)\(^{ }x^2-6x+11=0\)
D)(\(\left(x^2+2x+3\right)\left(x^2-25\right)\left(x+19\right)=0\)
a) \(\left(x+1\right)\left(2x-1\right)\left(-x+2\right)=0\)
\(\Leftrightarrow\left[\begin{matrix}x+1=0\\2x-1=0\\-x+2=0\end{matrix}\right.\Leftrightarrow\left[\begin{matrix}x=-1\\x=\frac{1}{2}\\x=2\end{matrix}\right.\)
Vậy phương trình có tập nghiệm là \(S=\left\{-1;\frac{1}{2};2\right\}\)
b) \(\left(2x-1\right)\left(3x+2\right)\left(4x-5\right)\left(x-7\right)=0\)
\(\Leftrightarrow\left[\begin{matrix}2x-1=0\\3x+2=0\\4x-5=0\\x-7=0\end{matrix}\right.\Leftrightarrow\left[\begin{matrix}x=\frac{1}{2}\\x=-\frac{2}{3}\\x=\frac{5}{4}\\x=7\end{matrix}\right.\)
Vậy phương trình có tập nghiệm là \(S=\left\{\frac{1}{2};-\frac{2}{3};\frac{5}{4};7\right\}\)
c) \(x^2-6x+11=0\)
\(\Leftrightarrow x^2-6x+9+2=0\)
\(\Leftrightarrow\left(x-3\right)^2+2=0\) (vô lí)
Vậy phương trình vô nghiệm
d) \(\left(x^2+2x+3\right)\left(x^2-25\right)\left(x+19\right)=0\)
\(\Leftrightarrow\left(x^2+2x+1+2\right)\left(x+5\right)\left(x-5\right)\left(x+19\right)=0\)
\(\Leftrightarrow\left[\left(x+1\right)^2+2\right]\left(x+5\right)\left(x-5\right)\left(x+19\right)=0\)
\(\Leftrightarrow\left[\begin{matrix}x+5=0\\x-5=0\\x+19=0\end{matrix}\right.\Leftrightarrow\left[\begin{matrix}x=-5\\x=5\\x=-19\end{matrix}\right.\)
Vậy phương trình có tập nghiệm là \(S=\left\{\pm5;-19\right\}\)
a,b,d dễ mà bạn tự làm
c,x2-6x+11=0<=> x2-6x+9+2=0
<=>(x-3)2=-2(vô lý)
vậy pt vô nghiệm