Question

1, Tìm x 

a, 4^2x-6=1

b, 5^x+ 5^x+1+5^x+2=775

Answer 1

CÁC BẠN GIÚP MÌNH NHA

Answer 2

MAI MÌNH ĐI HỌC RỒI NHA

Answer 3

a) 4^2x-6 = 1 = 4⁰

=> 2x - 6 = 0

=> 2x = 0 + 6

=> 2x = 6

=> x = 6 : 2

=> x = 3

Vậy x = 3

b) 5^x + 5^x+1 + 5^x+2 = 775

=> 5^x + 5^x.5 + 5^x.5² = 775

=> 5^x + 5^x.5 + 5^x.25 = 775

=> 5^x.(1 + 5 + 25) = 775

=> 5^x.31 = 775

=> 5^x = 775 : 31

=> 5^x = 25 = 5²

=> x = 2

Vậy x = 2

Answer 4

\(4^{2x-6}=1\Rightarrow2x-6=0\Rightarrow2x=6\Rightarrow x=\frac{6}{2}=3\)

 

 

 

Answer 5

a, 4^2x-6=1

\(\Rightarrow4^{2x-6}=4^0\)

\(\Rightarrow2x-6=0\)

\(\Rightarrow2x=6\)

\(\Rightarrow x=3\)​ 

Answer 6

b) 5x+ 5x+1+5x+2=775

\(\Rightarrow5^x+5^{x+1}+5^{x+2}=775\)

\(\Rightarrow5^x\left(1+5^1+5^2\right)=775\)

\(\Rightarrow5^x\cdot31=775\)

\(\Rightarrow5^x=25\)

\(\Rightarrow5^x=5^2\)

\(\Rightarrow x=2\)