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Examine whether the following numbers ...

Examine whether the following numbers are rational or irrational :
`(2sqrt3 + 3sqrt2) ^(2)`

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To determine whether the expression \((2\sqrt{3} + 3\sqrt{2})^2\) is rational or irrational, we will follow these steps: ### Step 1: Expand the Expression We start by expanding the expression using the formula \((a + b)^2 = a^2 + 2ab + b^2\). Let: - \(a = 2\sqrt{3}\) - \(b = 3\sqrt{2}\) Now, we can expand: \[ (2\sqrt{3} + 3\sqrt{2})^2 = (2\sqrt{3})^2 + 2(2\sqrt{3})(3\sqrt{2}) + (3\sqrt{2})^2 \] ### Step 2: Calculate Each Term Now, we calculate each term in the expansion: 1. \((2\sqrt{3})^2 = 4 \cdot 3 = 12\) 2. \(2(2\sqrt{3})(3\sqrt{2}) = 2 \cdot 2 \cdot 3 \cdot \sqrt{3} \cdot \sqrt{2} = 12\sqrt{6}\) 3. \((3\sqrt{2})^2 = 9 \cdot 2 = 18\) ### Step 3: Combine the Results Now we combine all the results from the previous step: \[ (2\sqrt{3} + 3\sqrt{2})^2 = 12 + 12\sqrt{6} + 18 \] \[ = 30 + 12\sqrt{6} \] ### Step 4: Determine Rationality Now we need to examine whether \(30 + 12\sqrt{6}\) is rational or irrational. - The number \(30\) is a rational number. - The term \(12\sqrt{6}\) involves \(\sqrt{6}\), which is known to be an irrational number because \(6\) is not a perfect square. Since the sum of a rational number and an irrational number is always irrational, we conclude that: \[ 30 + 12\sqrt{6} \text{ is irrational.} \] ### Final Conclusion Thus, the expression \((2\sqrt{3} + 3\sqrt{2})^2\) is an **irrational number**. ---
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