Solve the Equation involving $4^{\sqrt{log_2 x}}$

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SUMMARY

The equation $4^{\sqrt{\log_2 x}} \cdot 4^{\sqrt{\log_2 \frac{y}{2}}} \cdot 4^{\sqrt{\log_2 \frac{z}{4}}} \cdot 4^{\sqrt{\log_2 \frac{t}{2}}} = xyzt$ can be solved by expressing each variable in terms of parameters $a$, $b$, $c$, and $d$. The derived solutions are $x = 2$, $y = 4$, $z = 8$, and $t = 4$, under the constraints $0 < a \leq 2$, $0 < b \leq 1$, $0 < c \leq \frac{1}{2}$, and $0 < d \leq 1$. This leads to the conclusion that the product $a \cdot b \cdot c \cdot d$ must equal 1 for the equation to hold true.

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  • Understanding of logarithmic functions, specifically $\log_2$.
  • Familiarity with exponential equations and their properties.
  • Knowledge of algebraic manipulation involving square roots and products.
  • Basic comprehension of inequalities and their implications in real numbers.
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  • Explore exponential equations and their graphical representations.
  • Learn about inequalities and their role in defining solution sets in algebra.
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Find the real solution to the equation $4^{\sqrt{log_2 x}} \cdot 4^{\sqrt{log_2 \tiny \dfrac{y}{2}}}\cdot 4^{\sqrt{log_2 \tiny \dfrac{z}{4}}}\cdot 4^{\sqrt{log_2 \tiny \dfrac{t}{2}}}=xyzt$.
 
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## 4 ^ \sqrt { \log_2 x } \cdot 4 ^ \sqrt { \log_2 \frac y 2 } \cdot 4 ^ \sqrt { \log_2 \frac z 4 } \cdot 4 ^ \sqrt { \log_2 \frac t 2 } = x y z t ##

## ( a , b , c , d ) \in \{ ( e , f , g , h ) | ( e , f , g , h ) \in \mathbb R ^ 4 \wedge e \cdot f \cdot g \cdot h = 1 \} ##

## 4 ^ \sqrt { \log_2 x } \cdot 4 ^ \sqrt { \log_2 \frac y 2 } \cdot 4 ^ \sqrt { \log_2 \frac z 4 } \cdot 4 ^ \sqrt { \log_2 \frac t 2 } = a b c d \cdot x y z t ##
## 4 ^ \sqrt { \log_2 x } \cdot 4 ^ \sqrt { \log_2 \frac y 2 } \cdot 4 ^ \sqrt { \log_2 \frac z 4 } \cdot 4 ^ \sqrt { \log_2 \frac t 2 } = a x \cdot b y \cdot c z \cdot d t ##

## 4 ^ \sqrt { \log_2 x } = a x ##
## \sqrt { \log_2 x } \cdot \log_2 4 = \log_2 ( a x ) ##
## 2 \sqrt { \log_2 x } = \log_2 a + \log_2 x ##
## \log_2 x - 2 \sqrt { \log_2 x } + \log_2 a = 0 ##
## \sqrt { \log_2 x } = \frac { 2 \pm \sqrt { 4 – 4 \log_2 a } } { 2 } ##
## \sqrt { \log_2 x } = 1 \pm \sqrt { 1 – \log_2 a } ##
## \log_2 x = 1 \pm 2 \sqrt { 1 – \log_2 a } + 1 - \log_2 a ##
## x = 2 ^ { 2 \pm 2 \sqrt { 1 – \log_2 a } - \log_2 a } ##
## x = \frac 1 a \cdot 4 ^ { 1 \pm \sqrt { 1 – \log_2 a } } \wedge 0 \lt a \leq 2 ##

## 4 ^ \sqrt { \log_2 \frac y 2 } = b y ##
## \sqrt { \log_2 \frac y 2 } \cdot \log_2 4 = \log_2 ( b y ) ##
## 2 \sqrt { \log_2 \frac y 2 } = \log_2 b + \log_2 y ##
## \log_2 y - 2 \sqrt { \log_2 \frac y 2 } + \log_2 b = 0 ##
## y_1 = \frac y 2 ##
## \log_2 y_1 - 2 \sqrt { \log_2 y_1 } + \log_2 ( 2 b ) = 0 ##
## \sqrt { \log_2 y_1 } = \frac { 2 \pm \sqrt { 4 – 4 \log_2 ( 2 b ) } } { 2 } ##
## \sqrt { \log_2 y_1 } = 1 \pm \sqrt { 1 – \log_2 ( 2 b ) } ##
## \log_2 y_1 = 1 \pm 2 \sqrt { 1 – \log_2 ( 2 b ) } + 1 - \log_2 ( 2 b ) ##
## y_1 = 2 ^ { 2 \pm 2 \sqrt { 1 – \log_2 ( 2 b ) } - \log_2 ( 2 b ) } ##
## y_1 = \frac { 1 } { 2 b } \cdot 4 ^ { 1 \pm \sqrt {1 – \log_2 ( 2 b ) } } ##
## y = \frac 1 b \cdot 4 ^ { 1 \pm \sqrt { 1 – \log_2 ( 2 b ) } } \wedge 0 \lt b \leq 1 ##

## 4 ^ \sqrt { \log_2 \frac z 4 } = c z ##
## \sqrt { \log_2 \frac z 4 } \cdot \log_2 4 = \log_2 ( c z ) ##
## 2 \sqrt { \log_2 \frac z 4 } = \log_2 c + \log_2 z ##
## \log_2 z - 2 \sqrt { \log_2 \frac z 4 } + \log_2 c = 0 ##
## z_1 = \frac z 4 ##
## \log_2 z_1 - 2 \sqrt { \log_2 z_1 } + \log_2 ( 4 c ) = 0 ##
## \sqrt { \log_2 z_1 } = \frac { 2 \pm \sqrt { 4 – 4 \log_2 ( 4 c ) } } { 2 } ##
## \sqrt { \log_2 z_1 } = 1 \pm \sqrt { 1 – \log_2 ( 4 c ) } ##
## \log_2 z_1 = 1 \pm 2 \sqrt { 1 – \log_2 ( 4 c ) } + 1 - \log_2 ( 4 c ) ##
## z_1 = 2 ^ { 2 \pm 2 \sqrt { 1 – \log_2 ( 4 c ) } - \log_2 ( 4 c ) } ##
## z_1 = \frac { 1 } { 4 c } \cdot 4 ^ { 1 \pm \sqrt {1 – \log_2 ( 4 c ) } } ##
## z = \frac 1 c \cdot 4 ^ { 1 \pm \sqrt { 1 – \log_2 ( 4 c ) } } \wedge 0 \lt c \leq \frac 1 2 ##

## 4 ^ \sqrt { \log_2 \frac t 2 } = d t ##
## \sqrt { \log_2 \frac t 2 } \cdot \log_2 4 = \log_2 ( d t ) ##
## 2 \sqrt { \log_2 \frac t 2 } = \log_2 d + \log_2 t ##
## \log_2 t - 2 \sqrt { \log_2 \frac t 2 } + \log_2 d = 0 ##
## t_1 = \frac t 2 ##
## \log_2 t_1 - 2 \sqrt { \log_2 t_1 } + \log_2 ( 2 d ) = 0 ##
## \sqrt { \log_2 t_1 } = \frac { 2 \pm \sqrt { 4 – 4 \log_2 ( 2 d ) } } { 2 } ##
## \sqrt { \log_2 t_1 } = 1 \pm \sqrt { 1 – \log_2 ( 2 d ) } ##
## \log_2 t_1 = 1 \pm 2 \sqrt { 1 – \log_2 ( 2 d ) } + 1 - \log_2 ( 2 d ) ##
## t_1 = 2 ^ { 2 \pm 2 \sqrt { 1 – \log_2 ( 2 d ) } - \log_2 ( 2 d ) } ##
## t_1 = \frac { 1 } { 2 d } \cdot 4 ^ { 1 \pm \sqrt {1 – \log_2 ( 2 d ) } } ##
## t = \frac 1 d \cdot 4 ^ { 1 \pm \sqrt { 1 – \log_2 ( 2 d ) } } \wedge 0 \lt d \leq 1 ##

## ( 0 \lt a \leq 2 \wedge 0 \lt b \leq 1 \wedge 0 \lt c \leq \frac 1 2 \wedge 0 \lt d \leq 1 ) \Rightarrow 0 \lt a \cdot b \cdot c \cdot d \leq 1 ##
## a \cdot b \cdot c \cdot d = 1 \Rightarrow (a = 2 \wedge b = 1 \wedge c = \frac 1 2 \wedge d = 1) \Rightarrow x = 2 \wedge y = 4 \wedge z = 8 \wedge t = 4 ##
 

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