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## #1 2014-07-25 20:46:50

Guest

### Unit circle / Geometry

I know the basics of unit circle but I'm not even remotely aware about where to start with this problem. Any help pointing me in the right direction would be great. Cheers

## #2 2014-07-25 21:06:53

bob bundy
Registered: 2010-06-20
Posts: 8,137

### Re: Unit circle / Geometry

Welcome to the forum.

When AD is a diameter, the angle ABD will always be 90 (or pi/2) so that should get you started.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #3 2014-07-25 22:07:49

Nehushtan
Member
Registered: 2013-03-09
Posts: 905
Website

### Re: Unit circle / Geometry

It’s a unit circle so its radius is 1.

Last edited by Nehushtan (2014-07-25 23:44:19)

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## #4 2014-07-25 22:50:45

Member
Registered: 2014-05-04
Posts: 8

### Re: Unit circle / Geometry

bob bundy wrote:

Welcome to the forum.

When AD is a diameter, the angle ABD will always be 90 (or pi/2) so that should get you started.

Bob

Thanks Bob. It took me some time to figure out what the question was even asking. But together with your answer, the whole thing finally clicked.

PS Had problems logging in with my normal account for some reason. So just used a temp account to put that question up earlier.

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