IM 8.8.3 Lesson: Rational and Irrational Numbers

Find a positive solution to each equation:
Draw 3 squares of different sizes with vertices aligned to the vertices of the grid. Label the area. Label the side length.
Write an equation that shows the relationship between the side length and the area.
Are any of these numbers a solution to the equation[math]x^2=2[/math]? Explain your reasoning.[br][br][list][*][math]1[/math][/*][*][math]\frac{1}{2}[/math][/*][*][math]\frac{3}{2}[/math][/*][*][math]\frac{7}{5}[/math][/*][/list]
A rational number is a fraction or its opposite (or any number equivalent to a fraction or its opposite).
Find some more rational numbers that are close to [math]\sqrt{2}[/math].
Can you find a rational number that is exactly [math]\sqrt{2}[/math]?[br][br]
[size=150]If you have an older calculator evaluate the expression [math](\frac{577}{408})^2[/math] and it will tell you that the answer is 2, which might lead you to think that [math]\sqrt{2}=\frac{577}{408}[/math].[/size][br][br]Explain why you might be suspicious of the calculator’s result.
Find an explanation for why [math]408^2\cdot2[/math] could not possibly equal [math]577^2[/math]. How does this show that [math](\frac{577}{408})^2[/math] could not equal 2?
Repeat these questions for [math](\frac{1414213562375}{10000000000000})^2\ne2[/math]an equation that even many modern calculators and computers will get wrong.
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