Question

Bài 1:Tìm x N:a,4^x=2^x+1    b,16=(x-1)^4         c,(1+3+5+...+99)^2=(x-2)^2

Answer 1

\(\left(x-1\right)^4=16\)

\(\left(x-1\right)^4=2^4\)

\(\Rightarrow x-1=2\)

\(\Rightarrow x=3\)

vậy \(x=3\)

Answer 2

a, => 1 = 4^x-2^x = 2^x.(2^x-1)

=> 2^x=1 ; 2^x-1=0 ( vì 2^x >= 0 )

=> x=0

b, => (x-1)^4 = 16 = (-2)^4 = 2^4

=> x=-2 hoặc x=2

c, Xét : 1+3+5+....+99 = (1+99).50 : 2 = 2500

=> 2500^2 = (x-2)^2

=> x-2=2500 hoặc x-2=-2500

=> x=2502 hoặc x=2498

Tk mk nha

Answer 3

(x - 1)⁴ = 16

(x - 1)⁴ = 2⁴

=> x - 1 = 2

=> x = 3

Vậy x = 3