E not only can be irrational, it is.
why is e an irrational number
No, but it is an irrational number.
Any irrational number will, eg √2, π, e.
Yes, an irrational number divided by an irrational number will usually be an irrational number, but not always. For example, pi / (3pi) is 1/3, which is a rational number, but pi/e is an irrational number.
It depends on the base, but for either e or 10, it is irrational.
e
No, it is irrational. Furthermore, it is transcendental.
One, and e.
It is rational.
pi, the square root of 2, and e are all irrational numbers.
Euler's number, e = approx 2.71828
Nope. Quick example: e (2.71828) is irrational. Therefore 2*e is irrational making both of them elements of the set of irrational numbers. However, dividing the two, e/(2*e), gives you 1/2, which is a rational number.