0 is a real number.
No. The square root of negative one is an example of an imaginary (not real) number. Pi is irrational, but real.
The question is confusing. The additive inverse of a real number is the same number with the sign changed. For example, the additive inverse of -5 is +5 (or simply 5); the additive inverse of 7 (which is the same as +7) is -7.
2 is a real world prime number.
It need not be. For example, a complex number as a percent of most other complex numbers, or any real number, will not be a real number.
1/2, 5, pi, respectively
0 is a real number.
No. The square root of negative one is an example of an imaginary (not real) number. Pi is irrational, but real.
The question is confusing. The additive inverse of a real number is the same number with the sign changed. For example, the additive inverse of -5 is +5 (or simply 5); the additive inverse of 7 (which is the same as +7) is -7.
i
2 is a real world prime number.
Real
It need not be. For example, a complex number as a percent of most other complex numbers, or any real number, will not be a real number.
Yes, Any real number squared is a real number. In this case that number is 25.
Any real number (besides zero) divided by itself is equal to 1. In algebraic terms, if x is a non-zero real number then x/x=1. Zero is the exception because dividing a number by zero is undefined. For example 5 divided by itself is 1. 5/5=1
Since the imaginary parts cancel, and the real parts are the same, the sum is twice the real part of any of the numbers. For example, (5 + 4i) + (5 - 4i) = 5 + 5 + 4i - 4i = 10.
2.5 is an example.