The multiplication of two consecutive odd numbers is 6723, then the square…
2019
The multiplication of two consecutive odd numbers is 6723, then the square root of the smaller number is
- A.
91
- B.
9
- C.
7
- D.
729
Attempted by 6 students.
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Correct answer: B
Let the two consecutive odd numbers be x and x+2. Their product is given as 6723.
So, x(x+2) = 6723
This simplifies to: x² + 2x - 6723 = 0
Solve the quadratic equation using the quadratic formula: x = [-b ± √(b² - 4ac)] / 2a
Here, a = 1, b = 2, c = -6723
Discriminant D = b² - 4ac = 4 + 26892 = 26896
√D = √26896 = 164
x = [-2 ± 164] / 2
x = (162)/2 = 81 or x = (-166)/2 = -83
The smaller positive odd number is 81.
The square root of 81 is 9.
हिन्दी उत्तर:
माना दो क्रमागत विषम संख्याएँ x और x+2 हैं। उनका गुणनफल 6723 है।
इसलिए, x(x+2) = 6723
जिसका अर्थ है: x² + 2x - 6723 = 0
द्विघात समीकरण का उपयोग करके हल करें: x = [-b ± √(b² - 4ac)] / 2a
यहाँ, a = 1, b = 2, c = -6723
विविक्तकर D = b² - 4ac = 4 + 26892 = 26896
√D = √26896 = 164
x = [-2 ± 164] / 2
x = (162)/2 = 81 या x = (-166)/2 = -83
छोटी धनात्मक विषम संख्या 81 है।
81 का वर्गमूल 9 है।