Last updated on May 26th, 2025
If a number is multiplied by itself, the result is a square. The inverse of the square is a square root. The square root is used in various fields like physics, engineering, etc. Here, we will discuss the square root of -99.
The square root is the inverse of the square of the number. Since -99 is a negative number, its square root is not a real number. The square root of -99 is expressed in terms of the imaginary unit 'i'. In radical form, it is expressed as √-99, which can be rewritten as √99 * i. The value of √99 is approximately 9.95, so the square root of -99 is approximately 9.95i.
To find the square root of a negative number, we use the concept of imaginary numbers. The square root of -99 can be found by first finding the square root of 99 and then multiplying it by 'i'. Let us now learn the methods: Imaginary unit method
The imaginary unit method involves using 'i', where i² = -1. The square root of a negative number is found by taking the square root of its absolute value and multiplying by 'i'.
Step 1: Find the square root of 99, which is approximately 9.95.
Step 2: Multiply this value by 'i' to account for the negative sign inside the square root. Thus, the square root of -99 is approximately 9.95i.
The long division method can be used to find the square root of 99, which is a necessary step in finding √-99. Let us learn how to find the square root of 99 using the long division method, step by step:
Step 1: Group the digits of 99 as 99.
Step 2: Find a number whose square is less than or equal to 99. In this case, 9² = 81 is the closest.
Step 3: Subtract 81 from 99 to get 18.
Step 4: Bring down 00 to make it 1800.
Step 5: Double the divisor (9), which gives 18. Determine the next digit of the quotient such that 18n ≤ 1800.
Step 6: Continue the process to get the decimal value. The approximate value of √99 is 9.95.
The approximation method is another way to find the square root of 99. Here’s how to approximate the square root of 99:
Step 1: Identify the closest perfect squares. For 99, they are 81 (9²) and 100 (10²).
Step 2: 99 is closer to 100, so the square root of 99 is closer to 10 but slightly less.
Step 3: By interpolation, approximate the square root as 9.95. Thus, the square root of -99 is approximately 9.95i.
Students often make mistakes when dealing with negative square roots, especially with imaginary numbers. Here are common mistakes and how to avoid them.
Can you find the result of (√-99)²?
The result is -99.
The square of the square root of -99 is -99 itself, as (√-99)² = -99.
A quadratic equation x² + 99 = 0 needs solving. What are the solutions for x?
The solutions are x = ±9.95i.
By rearranging x² + 99 = 0, we get x² = -99. Therefore, x = √-99 = ±9.95i.
Calculate 2 × √-99.
The result is approximately 19.9i.
First, find √-99, which is approximately 9.95i, then multiply by 2. So, 2 × 9.95i ≈ 19.9i.
What is the square root of (-81 + 18)?
The square root is 0.
Calculate (-81 + 18) = -63. Since -63 is negative, the square root is imaginary: √-63 = ±√63i.
Find the perimeter of a square if its side length is √-99 units.
The perimeter is approximately 39.8i units.
Perimeter of a square = 4 × side length. Here, side length is √-99 ≈ 9.95i. Hence, the perimeter = 4 × 9.95i ≈ 39.8i units.
Jaskaran Singh Saluja is a math wizard with nearly three years of experience as a math teacher. His expertise is in algebra, so he can make algebra classes interesting by turning tricky equations into simple puzzles.
: He loves to play the quiz with kids through algebra to make kids love it.