Bài 1: Tìm n thuộc N:
\(2^{-1}\) x \(2^n\)+ 4 x\(2^n\)= 9x \(2^5\)
Bài 2: Tìm n thuộc N:
a) 3 < \(3^n\) < 234
b) \(4^{15}\)x\(9^{15}\) < \(2^n\)x\(3^n\) < \(18^{16}\)x\(2^{16}\)
Bài 3: Tìm x:
a) \(\left(2x-1\right)^4\)= 81
b) \(\left(x-2\right)^2\)=1
c) \(x^{2000}\)=\(x\)
d) \(\left(4x-3\right)^3\)= -125
Giúp mk với nhé, ai nhanh mk tick cho, CẢM ƠN NHÌU!!!!!!!!!!!!!
Bài 3: Tìm x:
a. \(\left(2x-1\right)^4=81\)
\(\Rightarrow\left(2x-1\right)^4=3^4\)
=> 2x - 1 = 3
=> 2x = 4
=> x = 2
b. \(\left(x-2\right)^2=1\)
\(\Rightarrow\) \(\left(x-2\right)^2=1^2\)
=> x - 2 = 1
=> x = 3
c. \(x^{2000}=x\)
=> x = 1
d. \(\left(4x-3\right)^3=-125\)
\(\Rightarrow\left(4x-3\right)^3=\left(-5\right)^3\)
=> 4x - 3 = -5
=> 4x = -2
=> x = \(\dfrac{-1}{2}\)
