a: \(1=4^0\)

\(4=4^1\)

\(16=4^2\)

\(256=4^4\)

b: \(\dfrac{1}{4}=4^{-1}\)

\(\dfrac{1}{64}=4^{-3}\)

\(\dfrac{1}{256}=4^{-4}\)

\(\dfrac{1}{16}=4^{-2}\)

\(\dfrac{1}{1024}=4^{-5}\)

64\(^x\) : 16\(^x\) = 256

(64: 16)^\(x\)  = 256

        4\(^x\)  = 4⁴

          \(x\) = 4

Vậy \(x\) = 4

A=39760. b=158692,1211

64^x.16^x=256¹²:1024

1024^x=4⁴³

4^5x=4⁴³

5x=43

x=8,6

\(64^x.16^x=256^{12}:1024\)

\(\Rightarrow\) \(\left(4^3\right)^x.\left(4^2\right)^x=\left(4^4\right)^{12}:4^5\)

\(\Rightarrow\) \(4^{3x}.4^{2x}=4^{48}:4^5\)

\(\Rightarrow\) \(4^{3x+2x}=4^{43}\)

\(\Rightarrow\) \(3x+2x=43\)

\(\Rightarrow\) \(\left(3+2\right)x=43\)

\(\Rightarrow\) \(5x=43\)

\(\Rightarrow\) \(x=\frac{43}{5}\)

64^x.16^x=256¹²:1024

1024^x=4⁴³

4^5x=4⁴³

5x=43

x=8,6

(-3/4)63x-1=(3/4)^3

3x-1=3+1

3x=3=1

x=4;3

x=4/3

Vậy x=4/3

25556

a.1025

mk chịu câu b

*** mk nha

ko bít lm bài này ak! dễ mak

bày cho câu b nha!

umk

256 x 6=512 x 3

512 x 3=256 x 6

999 x 2>1000

512 x 5>1024

1024<512 x 5

1024=512 x 2

512=256 x 2

256=128 x 2

128=64 x 2

64=32 x 2

32=16 x 2

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