The question doesn't really make sense. All numbers fall into the category of 'complex'. As far as rational or not rational (irrational), that is not exclusive of being complex (or imaginary).
9 is a rational number
They can be rational, irrational or complex numbers.They can be rational, irrational or complex numbers.They can be rational, irrational or complex numbers.They can be rational, irrational or complex numbers.
-1/9 is rational because it can be expressed as a fraction (ratio).
Any number - integer, rational, irraational, complex - can multiply 27.
It is 9, though if you must have it in the form of a ratio, you could try 9/1.
It's rational. It's the ratio of -1 to 9 .
yes
Yes, the square root of 1 is 1.
Yes.
An irrational number cannot be written as a fraction or a whole number,Like Pi for example
Out of the numbers,9, 10, 1, and 4,no number is irrational.Each of these numbers can be written in the form p/q (p,q = Z ; q not equal to 0).9 = 9/1, 10 = 10/1, 1 = 1/1 and 4 = 4/1So, all these numbers are rational. and none of these numbers is 'not a rational number'.
It is 1, as it is for all complex numbers - which includes real numbers.