Question

Tìm x

2^x + 2^{x+1 +} 2^x+2 =224

Làm ơn giúp mình nha,bn nào trả lới nhanh nhất cho 5 like,mai mình phải nộp rồi mong các bn giúp

Answer 1

Ta có:

\(2^x+2^{x+1}+2^{x+2}=224\)

\(\Rightarrow2^x+2^x.2+2^x.2.2=224\)

\(\Rightarrow2^x\left(1+2+4\right)=224\)

\(\Rightarrow2^x=224\div\left(1+2+4\right)\)

\(\Rightarrow2^x=32\)

\(\Rightarrow2^x=2^5\Rightarrow x=5\)

Vậy \(x=5\)

Answer 2

2^x + 2^{x + 1} + 2^{x + 2} = 224

2^x + 2^x . 2 + 2^x . 2² = 224

2^x( 1 + 2 + 4 ) = 224

2^x . 7 = 224

\(\Rightarrow\)2^x = 224 : 7

\(\Rightarrow\)2^{x =} 32

\(\Rightarrow\)2^x = 2⁵

^{\(\Rightarrow\)}x = 5

Vậy ..

Answer 3

2^x + 2^x+1 + 2^x+2 =224

=>2^x ( 1+2+2²) =224

=> 2^x . 7 =224

=> 2^x =32

=>2^x = 2⁵

=>x =5

Answer 4

\(2^x+2^{x+1}+2^{x+2}=224\)

\(2^x+2^{x+1}+2^{x+2}=224\)\(2^x+2^{x+1}+2^{x+2}=224\)⇔ \(2^x+2^x.2+2^x.2^2=224\)

⇔ \(2^x\left(1+2+2^2\right)=224\)

⇔ \(2^x.7=224\)

⇔ \(2^x=224:7\)

⇔ \(2^x=32\)

⇔ \(2^x=2^5\)

⇒ \(x=5\)