Rafael Bombelli defined imaginary numbers in 1572, and Descartes named them 'imaginary' in 1637. It wasn't until the work of Euler in the 1700's that a usefulness for imaginary numbers was found, though. See the Wikipedia articles I linked for some good information on imaginary and complex numbers. I also linked an explanatory video that is pretty good as well.
No. Irrational numbers are real numbers, therefore it is not imaginary.
Real numbers are numbers that can be found on the number line. This includes both the rational and irrational numbers. The Real Numbers did not have a name before Imaginary Numbers were thought of. They got called "Real" because they were not Imaginary.
Imaginary numbers are not a subset of the real numbers; imaginary means not real.
Yes, imaginary numbers are a subset of complex numbers.
No difference. The set of complex numbers includes the set of imaginary numbers.
No, it is imaginary. Irrational numbers are a subset of real numbers Real numbers and imaginary numbers are sets without any overlap.
examples: 1, 2, 0, -5, sqrt(2), pi etc. real numbers means numbers on the real plane. the opposite of real numbers are imaginary numbers which takes the format of ai, in which the i is the imaginary unit they do not exist on the real plane, but only on the imaginary plane. they can be found by square-rooting a negative number, e.g. sqrt(-4)=2i usually imaginary numbers are used with real numbers, with the format a+bi, and this is called complex numbers.
imaginary numbers are numbers that are a negative square root, which is not possoble therefor it is called and imaginary number. ex the square root of -24 is an imaginary number
2 does belong to the set of imaginary numbers. Any real number is also imaginary. Imaginary numbers are the set of all numbers that can be expressed as a +b*i where "i" is the square root of negative one and "a" and "b" are both real numbers.
An imaginary number is symbolized by the letter i
Imaginary numbers are only ever used when you are using the square roots of negative numbers. The square root of -1 is i. You may find imaginary numbers when you are finding roots of equations.