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How to open a square root in junior high school mathematics
Manual square root

1. Divide the integer part of the square root into a section from the unit to the left every two digits, separate it with apostrophe, and divide it into several sections, indicating how many digits the square root is; The decimal part is separated from the highest digit to the last two digits, and the number of segments shall meet the accuracy requirements of+1. 2. According to the number in the first paragraph on the left, find the number with the highest square root. (In the example on the right, the square number less than 5 is 4, so the highest bit of the square root is 2. 3. Subtract the square of the highest digit from the number in the first paragraph, and write the number in the second paragraph to the right of their difference to form the first remainder. 4. Multiply the highest digit obtained in the second step by 20 to try to divide the first remainder, and the largest integer obtained is used as the trial quotient. (The quotient in the right figure is [152/(2×20)]=[3.8]=3. ) 5. Multiply this quotient by 20 of the highest digit obtained in the second step, and then multiply it by the quotient. If the product is less than or equal to the remainder, the quotient is the second digit of the square root; If the product obtained is greater than the remainder, try again by reducing the quotient, and the first quotient obtained is less than the remainder of the second number as the square root. (that is, 3 is the second place of the square root. ) 6. In the same way, continue to look for numbers on other bits of the square root. Subtract the product obtained by the above method from the last remainder (i.e. 152- 129 = 23) to form a new remainder of the third segment number (i.e., 2325). To find the trial quotient, multiply the first two digits of the square root (that is, 23) obtained above by 20, and try to divide it by the new remainder (2325), and the largest integer obtained is the new trial quotient. The integer part of (2325/(23×20) is 5. ) 7. The inspection of the new tester is the same as before. (In the example on the right, the last remainder is 0, which is just used up, so 235 is the square root. )