x=t-2sint, y=1-2cost

show that the curve crosses the x axis where t=pi/3 and t=5pi/3

I understand that you have to solve y=0 but alli can get is t=pi/3

can't you just put both t's into the equation for y and show that y = 0 and therefor it's crossing the x axis?

Always graph if at all possible.

I could but I don't have access to a graph creator and no be cause that would be the wrong way of answering that qn and I wouldn't get marks, I have to solve y=0 which makes cost=1/2 which makes t=pi/3 but I cannot find out how to make it also equal 5pi/3

I'd say get familiar with the unit circle. This is the properties of the trig functions you should know.







If C=0, then

If C=1, then

If C=2, then

and so on...

Though, anything that exceeds 2Pi you probably can disregard.

Thank you, guess I need to read up on my C3 then