# To build a complex polynomial

For example I have this polynomiyal:

```
p=(z-2*I)*(z+1*I)
```

I want sage show me someting like:

```
z^2-z*(1*I)-2
```

It doesn't mind the number of roots.

To build a complex polynomial

**
asked 2016-01-17 20:22:11 +0100 **

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For example I have this polynomiyal:

```
p=(z-2*I)*(z+1*I)
```

I want sage show me someting like:

```
z^2-z*(1*I)-2
```

It doesn't mind the number of roots.

add a comment

1

Is that what you want?

```
sage: var('z')
sage: p=(z-2*I)*(z+1*I)
sage: p.expand()
z^2 - I*z + 2
```

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Asked: ** 2016-01-17 20:22:11 +0100 **

Seen: **125 times**

Last updated: **Jan 17 '16**

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