Tangible refers to things we can see and feel whereas intangible are things that cannot be seen or felt. Let us understand this by an example. Suppose the cost of doing an MBA course from a top business schools is $100000 while the cost of a low rung school is $50000.
Complex numbers have both a real number element and an imaginary number element, usually in the form a + bi. In this form, a and b are real numbers, while i is an imaginary number. An imaginary number is the designation given for the square root of negative one. Many careers that employ higher mathematics also use complex numbers, which can help simplify mathematical equations that would otherwise be much longer.
The real number a is called the real part of the complex number a + bi; the real number b is called the imaginary part of a + bi. By this convention the imaginary part does not include the imaginary unit: hence b, not bi, is the imaginary part.