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Evaluate sqrt (42.25). sqrt( 1.96). s...

Evaluate `sqrt (42.25).`
`sqrt( 1.96).` ` sqrt(6.4009).`
`sqrt (0.4225).` `sqrt2` correct up to two piaces of dectimal.
sqrt (0.8)` correct up to two phase of decimal.

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To evaluate the square roots of the given numbers, we will use the long division method. Let's go through each part step by step. ### Step 1: Evaluate `sqrt(42.25)` 1. **Pair the digits**: Start from the decimal point and pair the digits. Here, we have (42)(25). 2. **Find the largest square**: The largest square less than or equal to 42 is 36 (which is \(6^2\)). So, we write down 6. 3. **Subtract**: \(42 - 36 = 6\). 4. **Bring down the next pair**: Bring down 25 to get 625. 5. **Double the quotient**: Double 6 to get 12. Now, we need to find a digit \(x\) such that \(12x \cdot x \leq 625\). Testing \(x = 5\), we find \(125 \cdot 5 = 625\). 6. **Subtract**: \(625 - 625 = 0\). 7. **Result**: Therefore, \( \sqrt{42.25} = 6.5\). ### Step 2: Evaluate `sqrt(1.96)` 1. **Pair the digits**: Pair the digits as (1)(96). 2. **Find the largest square**: The largest square less than or equal to 1 is 1 (which is \(1^2\)). So, we write down 1. 3. **Subtract**: \(1 - 1 = 0\). 4. **Bring down the next pair**: Bring down 96 to get 96. 5. **Double the quotient**: Double 1 to get 2. Now, we need to find a digit \(x\) such that \(2x \cdot x \leq 96\). Testing \(x = 4\), we find \(24 \cdot 4 = 96\). 6. **Subtract**: \(96 - 96 = 0\). 7. **Result**: Therefore, \( \sqrt{1.96} = 1.4\). ### Step 3: Evaluate `sqrt(6.4009)` 1. **Pair the digits**: Pair the digits as (6)(40)(09). 2. **Find the largest square**: The largest square less than or equal to 6 is 4 (which is \(2^2\)). So, we write down 2. 3. **Subtract**: \(6 - 4 = 2\). 4. **Bring down the next pair**: Bring down 40 to get 240. 5. **Double the quotient**: Double 2 to get 4. Now, we need to find a digit \(x\) such that \(4x \cdot x \leq 240\). Testing \(x = 5\), we find \(45 \cdot 5 = 225\). 6. **Subtract**: \(240 - 225 = 15\). 7. **Bring down the next pair**: Bring down 09 to get 1509. 8. **Double the quotient**: Double 25 to get 50. Now, we need to find a digit \(x\) such that \(50x \cdot x \leq 1509\). Testing \(x = 3\), we find \(53 \cdot 3 = 159\) which is too high. Testing \(x = 2\), we find \(52 \cdot 2 = 104\). 9. **Subtract**: \(1509 - 104 = 1405\). 10. **Result**: Therefore, \( \sqrt{6.4009} \approx 2.53\). ### Step 4: Evaluate `sqrt(0.4225)` 1. **Pair the digits**: Pair the digits as (0)(42)(25). 2. **Find the largest square**: The largest square less than or equal to 0 is 0. So, we write down 0. 3. **Bring down the next pair**: Bring down 42 to get 42. 4. **Find the largest square**: The largest square less than or equal to 42 is 36 (which is \(6^2\)). So, we write down 6. 5. **Subtract**: \(42 - 36 = 6\). 6. **Bring down the next pair**: Bring down 25 to get 625. 7. **Double the quotient**: Double 6 to get 12. Now, we need to find a digit \(x\) such that \(12x \cdot x \leq 625\). Testing \(x = 5\), we find \(125 \cdot 5 = 625\). 8. **Subtract**: \(625 - 625 = 0\). 9. **Result**: Therefore, \( \sqrt{0.4225} = 0.65\). ### Step 5: Evaluate `sqrt(2)` 1. **Use long division method**: Start with 2. Pair it as (2)(00). 2. **Find the largest square**: The largest square less than or equal to 2 is 1 (which is \(1^2\)). So, we write down 1. 3. **Subtract**: \(2 - 1 = 1\). 4. **Bring down the next pair**: Bring down 00 to get 100. 5. **Double the quotient**: Double 1 to get 2. Now, we need to find a digit \(x\) such that \(2x \cdot x \leq 100\). Testing \(x = 4\), we find \(24 \cdot 4 = 96\). 6. **Subtract**: \(100 - 96 = 4\). 7. **Bring down the next pair**: Bring down 00 to get 400. 8. **Double the quotient**: Double 14 to get 28. Now, we need to find a digit \(x\) such that \(28x \cdot x \leq 400\). Testing \(x = 1\), we find \(281 \cdot 1 = 281\). 9. **Subtract**: \(400 - 281 = 119\). 10. **Result**: Therefore, \( \sqrt{2} \approx 1.41\). ### Step 6: Evaluate `sqrt(0.8)` 1. **Pair the digits**: Pair the digits as (0)(80). 2. **Find the largest square**: The largest square less than or equal to 0 is 0. So, we write down 0. 3. **Bring down the next pair**: Bring down 80 to get 80. 4. **Find the largest square**: The largest square less than or equal to 80 is 64 (which is \(8^2\)). So, we write down 8. 5. **Subtract**: \(80 - 64 = 16\). 6. **Bring down the next pair**: Bring down 00 to get 1600. 7. **Double the quotient**: Double 8 to get 16. Now, we need to find a digit \(x\) such that \(16x \cdot x \leq 1600\). Testing \(x = 9\), we find \(169 \cdot 9 = 1521\). 8. **Subtract**: \(1600 - 1521 = 79\). 9. **Result**: Therefore, \( \sqrt{0.8} \approx 0.89\). ### Summary of Results: - \( \sqrt{42.25} = 6.5 \) - \( \sqrt{1.96} = 1.4 \) - \( \sqrt{6.4009} \approx 2.53 \) - \( \sqrt{0.4225} = 0.65 \) - \( \sqrt{2} \approx 1.41 \) - \( \sqrt{0.8} \approx 0.89 \)
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