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121 LearnersLast updated on December 15, 2025

The square root is the inverse operation of squaring a number. When dealing with negative numbers, the square root involves imaginary numbers. The concept of square roots is used in various fields like engineering, physics, and mathematics. Here, we will discuss the square root of -625.
The square root is the inverse operation of squaring a number.
Since -625 is a negative number, its square root involves the imaginary unit 'i', where i² = -1.
The square root of -625 is expressed in terms of imaginary numbers.
It can be written as √(-625) = √(625) × i = 25i, where 'i' is the imaginary unit.
The concept of square roots for negative numbers introduces imaginary numbers.
The square root of a negative number is not defined in the set of real numbers but is defined in the set of complex numbers.
Let us explore the following points: Imaginary unit 'i' Expressing the square root of negative numbers Applications of imaginary numbers
To express the square root of a negative number:
Step 1: Identify the positive counterpart of the number. For -625, the positive counterpart is 625.
Step 2: Calculate the square root of 625, which is 25.
Step 3: Multiply the square root of the positive number by 'i', the imaginary unit.
Thus, √(-625) = 25i.


Imaginary numbers have applications in various fields, including electrical engineering, signal processing, and quantum physics.
Imaginary numbers help in solving equations that do not have real solutions and are used to express complex concepts in these fields.
When dealing with square roots of negative numbers, it is essential to understand the role of the imaginary unit.
Here are some common mistakes to avoid:
Not recognizing the imaginary unit 'i'.
Forgetting to multiply the positive square root by 'i'.
Confusing the properties of real and imaginary numbers.
Students may make errors while working with square roots of negative numbers, especially when involving imaginary numbers.
Let's explore some common mistakes:
What is the square root of -625 in terms of imaginary numbers?
The square root of -625 is 25i.
To find the square root of -625, recognize that it involves the imaginary unit 'i'.
The square root of 625 is 25, so the square root of -625 is 25i.
How do you express the square root of -625 using the imaginary unit?
The square root of -625 is expressed as 25i.
The imaginary unit 'i' is used to represent the square root of negative numbers.
The square root of 625 is 25, so √(-625) is expressed as 25i.
If x = โ(-625), what is xยฒ?
x² = -625.
If x = √(-625), then x = 25i.
Therefore, x² = (25i)² = 625 × i² = 625 × (-1) = -625.
What is the principal square root of -625?
The principal square root of -625 is 25i.
The principal square root refers to the non-negative square root.
However, for negative numbers, we use the imaginary unit 'i'.
Thus, the principal square root of -625 is 25i.

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.






