## Help please if possible,how to put these questions into matlab programming language?

### Amanda Kit Ting (view profile)

on 6 Oct 2013
Latest activity Commented on by Amanda Kit Ting

on 8 Oct 2013

### Image Analyst (view profile)

Don't help me to solve just needed guidance of how to put it into programming code.

a) Calculate and plot the ideal gas pressure as a function of volume for a given temperature. Mathematically, the operations can be written as shown below: (what does this question means?)

```                           R = 8.31453Jmol-1K-1
T = 273.15K
N = 7mol
v = (0.1m3,0.3m3,…,1.5m3)
e = (1,1,…,1)T
t = Te
P = NRdiag(v)-1t    ```
```(b)	 Plot an exponentially decaying sine plot = e-0.4xsinx, 0 < x < 4π, taking 10, 50, and 100 points in the interval.
[Be careful about computing y. You need array multiplication between e-0.4x  and sin(x)](what does a exponentially decaying sine plot looks like?)
```
```(c)	Let h(t)= <x, y, t > where x =t cos(t), y = t sin(t) for -10π ≤ t ≤ 10π be the space curve. Plot its graph over the indicated interval using 3d plot. (How to make a plot to become a 3d graph?)
```

Walter Roberson

### Walter Roberson (view profile)

on 6 Oct 2013

The notation is mathematical rather than programming.

NRdiag(v)-1t represents N * R * inv( diag(v) ) * t

where diag(v) is the MATLAB operator for constructing a full matrix with the given vector on its main diagonal.

I believe

```e = (1,1,…,1)T
```

represents the transpose of the row vector [1,1,...1], and that

```t = Te
```

represents t = T * e where T is the constant given and e is the transposed row vector.

Image Analyst

### Image Analyst (view profile)

on 7 Oct 2013

That is confusing if T = transpose and T also equals temperature. But maybe she just couldn't reproduce superscripts like a small T in the editor.

Amanda Kit Ting

### Amanda Kit Ting (view profile)

on 8 Oct 2013

Hi guys,

the t in the operation e = (1,1,…,1)T is suppose to be transcipt.

and following the hints that you guys shown,

i've got the solution at matlab.

appreciate it.

### Image Analyst (view profile)

on 6 Oct 2013

A hint for (b): they mean to use .* instead of * to do element by element multiplication instead of matrix multiplication. Same hint for (c). Another hint: linspace() function.

Amanda Kit Ting

on 8 Oct 2013