\(\dfrac{x-1}{8}=\dfrac{2}{x-1}\\ \left(x-1\right)^2=16=4^2=\left(-4\right)^2\\ \left[{}\begin{matrix}x-1=4\\x-1=-4\end{matrix}\right.\left[{}\begin{matrix}x=5\\x=-3\end{matrix}\right.\)
\(\dfrac{x-1}{8}=\dfrac{2}{x-1}\\ \left(x-1\right)^2=16=4^2=\left(-4\right)^2\\ \left[{}\begin{matrix}x-1=4\\x-1=-4\end{matrix}\right.\left[{}\begin{matrix}x=5\\x=-3\end{matrix}\right.\)
tìm x biết
1) x=-1/2 + 3/4 2) x - 1/5 = 2/11 3) x - 5/6 = 16/42 + -8/56
4) x/5 = 5/6 + -19/30 5) |x| - 1/4 = 6/18 6)x = -1/2 +3/4
7) x/15 = 3/5 + -2/3 8)11/8 + 13/6 = 85/x 9) x - 7/8 = 13/12
10) x - -6/15 = 4/27 11) -\(\dfrac{-6}{12}\)+ x = 9/48 12) x - 4/6 = 5/25 + -7/15
tìm nghiệm
G(x)=8(x+1^3+1
H(x)=8/9-2(x-1)^2
K(x)=(x+8)(x^2-9/25)
\(b) 5^{x+4} - 3 . 5^{x+3} = 2. 5^{11} \)
\(c) 2 . 3^{x+2} + 4 . 3^{x+1} = 10 . 3 ^{6}\)
\(d) 6 . 8 ^ {x-1} + 8 ^ {x+1} = 6 . 8^ {19} + 8 ^ {21}\)
\(\frac{1}{1-x}+\frac{1}{1+x}+\frac{2}{1+x^2}+\frac{4}{1+x^4}+\frac{8}{1+x^8}+\frac{16}{1+x^{16}}\)
1/Tính :
a. A= 1/17+ 7/17.27 + 7/27.37 + .................... +7/1997.2007
b. B=-1/2007.2006 - 1/2005.2006 - 1/2005.2004 - .................... - 1/3.2 - 1/2.1
2/Tim x biết :
2/(x+2)(x+4) + 4/(x+4)(x+8) + 6/(x+8)(x+14) = x/(x+2)(x+14)
Với x không thuộc tập hợp {-2;-4;-6;-8;-14}
tìm x biết (-8+x^2)(-8+x^2)(-8+x^2)(-8+x^2)(-8+x^2)=1
Tìm x biết:
a) 6* 8^x-1 + 8^x+1 = 6* 8^19 + 8^21
b) 4* 3^x-1 + 2* 3^x+2 = 4* 3^6 +2* 3^9
.A) x/x+1=1/2 , B) x/2=x/3 , C) x+1/2=x+1/2017, i)3/x=x/2017 , O) x:3=x+1/2 , m) x+1/2=x+2/3 ,P) x+1/2=x , M) 2/x=x/8 , Q) x2/2=8/x2 , r) x3/2=32/x
Tìm x
1/ (x - 1/2)^3 = 8
2/ (x - 1)^3 = 8/27
3/ (x - 2/3)^x = 1/81