1. ## Trigonometry Help!

Could someone please explain to me how to do this question? I just what to understand what to do.The question confuses me for some reason so I don't know how to begin...... Thank-you

2. Hello June78

Welcome to Math Help Forum!
Originally Posted by June78
Could someone please explain to me how to do this question? I just what to understand what to do.The question confuses me for some reason so I don't know how to begin...... Thank-you
We are asked to start to record the height of the stone as soon as it becomes stuck. So at $0^o$, the height is $0$ cm - the stone is still at ground level.

After $\tfrac14$ revolution $(90^o)$, the stone will be level with the centre of the wheel, so it will be $30$ cm above the ground.

Continue in the same way. At $180^o$ it will be at the top of the wheel, so it's ...? cm above the ground.

When you come to sketch the graph, you'll need to consider 2 complete revolutions of the wheel. You'll get a graph similar to the ones here.