What are the integer values for x, y, z, a, b, c in the equation?

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In summary, the values of a, b, c, x, y, z in a mathematical equation can be found through methods such as substitution, elimination, or graphing. Finding these values is important for understanding and solving real-world problems, and the values can change depending on the conditions or variables in the equation. Common methods for finding these values include substitution, elimination, graphing, and using the quadratic formula. To check the accuracy of the found values, one can substitute them back into the original equation and verify equality or use mathematical tools for verification.
  • #1
anemone
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Given that $1+\sqrt{2}+\sqrt{2(2+\sqrt{2})}=\sqrt{\dfrac{x+\sqrt{y+\sqrt{z}}}{a-\sqrt{b+\sqrt{c}}}}$, where $x,\,y,\,z,\,a,\,b,\,c$ are integers. Find the values for all of integers $x,\,y,\,z,\,a,\,b,\,c$.
 
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  • #2
Hint:

Note that for example if we have $36+20 \sqrt{2}+8 \sqrt{2+\sqrt{2}}+4 \sqrt{2 (2+\sqrt{2}})$, it can be factorized as $(4+2\sqrt{2})(8+\sqrt{2}+2\sqrt{2+\sqrt{2}})$.

Also:

$2=(2+\sqrt{2})(2-\sqrt{2})$.
 
  • #3
My solution:

$1+\sqrt{2}+\sqrt{2(2+\sqrt{2})}=\sqrt{\dfrac{x+\sqrt{y+\sqrt{z}}}{a-\sqrt{b+\sqrt{c}}}}$

Squaring it gives

$7+4\sqrt{2}+2\sqrt{2(2+\sqrt{2})}+4\sqrt{2+\sqrt{2}}=\dfrac{x+\sqrt{y+\sqrt{z}}}{a-\sqrt{b+\sqrt{c}}}$

If we let

$\begin{align*}7+4\sqrt{2}+2\sqrt{2(2+\sqrt{2})}+4\sqrt{2+\sqrt{2}}&=(a(2+\sqrt{2})(b+c\sqrt{2}+d\sqrt{2+\sqrt{2}})\\&=2ab+2ac+(ab+2ac)\sqrt{2}+ad\sqrt{2(2+\sqrt{2})}+2ad\sqrt{2+\sqrt{2}}\end{align*}$

Equating the coefficients and constant give

$ad=2$, $ab=3$ and if we let $a=1$, it then suggests that $d=2$, $b=3$ and $c=\dfrac{1}{2}$

$\begin{align*}\therefore 7+4\sqrt{2}+2\sqrt{2(2+\sqrt{2})}+4\sqrt{2+\sqrt{2}}&=\left(\dfrac{1}{2}(2+\sqrt{2})(6+\sqrt{2}+4\sqrt{2+\sqrt{2}}\right)\\&= \dfrac{(2+\sqrt{2})(6+\sqrt{2}+4\sqrt{2+\sqrt{2}})}{2}\\&= \dfrac{(2+\sqrt{2})(6+\sqrt{2}+4\sqrt{2+\sqrt{2}})}{(2+\sqrt{2})(2-\sqrt{2})}\\&=\dfrac{6+\sqrt{2}+4\sqrt{2+\sqrt{2}}}{2-\sqrt{2}}\\&\end{align*}$

Now, the tricky part is to recognize that $2-\sqrt{2}=(2+\sqrt{2+\sqrt{2}})(2-\sqrt{2+\sqrt{2}})$, and also, $6+\sqrt{2}+4\sqrt{2+\sqrt{2}}=2^2+2(2)\sqrt{2+\sqrt{2}}+\sqrt{2+\sqrt{2}}^2=(2+\sqrt{2+\sqrt{2}}) ^2$

$\begin{align*}\therefore 7+4\sqrt{2}+2\sqrt{2(2+\sqrt{2})}+4\sqrt{2+\sqrt{2}}&=\dfrac{(2+\sqrt{2+\sqrt{2}}) ^2}{(2+\sqrt{2+\sqrt{2}})(2-\sqrt{2+\sqrt{2}})}\\&=\dfrac{2+\sqrt{2+\sqrt{2}}}{2-\sqrt{2+\sqrt{2}}}\\&=\sqrt{\dfrac{x+\sqrt{y+\sqrt{z}}}{a-\sqrt{b+\sqrt{c}}}}\end{align*}$

So, $a=b=c=x=y=z=2$.
 

Related to What are the integer values for x, y, z, a, b, c in the equation?

1. How do you find the value of a, b, c, x, y, z in a mathematical equation?

The values of a, b, c, x, y, z in a mathematical equation can be found by using algebraic methods such as substitution, elimination, or graphing. These methods involve manipulating the given equation to isolate the desired variable and then solving for its value.

2. What is the importance of finding the values of a, b, c, x, y, z in a mathematical equation?

Finding the values of a, b, c, x, y, z in a mathematical equation is important because it allows us to understand and solve real-world problems, make predictions, and make informed decisions. It also helps us to better understand the relationships and patterns between variables in the equation.

3. Can the values of a, b, c, x, y, z in a mathematical equation change?

Yes, the values of a, b, c, x, y, z in a mathematical equation can change depending on the given conditions or variables in the equation. For example, in a linear equation, changing the slope or y-intercept will result in different values for x and y.

4. What are some common methods for finding the values of a, b, c, x, y, z in a mathematical equation?

Some common methods for finding the values of a, b, c, x, y, z in a mathematical equation include substitution, elimination, graphing, and using the quadratic formula. Other methods may also be used depending on the specific type and complexity of the equation.

5. How can I check if the values of a, b, c, x, y, z that I have found are correct?

You can check the values of a, b, c, x, y, z that you have found by substituting them back into the original equation and verifying that both sides of the equation are equal. You can also use a calculator or other mathematical tools to check your work and ensure accuracy.

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