# All Questions

44 views

### Integral calculation - where the $i$ came from?

$$\frac{e^{it(c-n)}}{i(c-n)} |_{-\pi}^\pi = \frac{e^{i\pi(c-n)} - e^{-i\pi(c-n)}}{i(c-n)} =\frac{2\sin(\pi(c-n))}{i(c-n)}$$ Correct answer is:$$\frac{2\color{red}{i}\sin(\pi(c-n))}{i(c-n)}$$ Why? :/...
189 views

### How would you prove this theory of computation problem?

I have trouble proving the following statement, I'm supposed to do it for our theory of computation course but since I've been trying for days I'm looking for a hint : What is the smallest value ...
67 views

94 views

### Marbles in a bag (Combinatorics)

There are 10 numbered from 1 to 10 marbles. The marbles are placed in an opaque bag and shuffled. One random marble is taken out, its number is written on a piece of paper, marble is then returned to ...
19 views

### Simple odds calculation

I'm stuck with a simple expression creation problem. I'd like to express odds by removing values from $100$ and arriving at a number. Every variable I use has value, that can either be $+10$ or $-10$, ...
84 views