Hello Salt

Welcome to Math Help Forum!The equation you need will be in the formwhereis the height above ground in metresYou won't be able to solve this completely (you haven't been given enough information) but you can get a set of possible solutions. Here's how:

is the time in seconds

are constants

takes values between and for all values of , so in the equation above, takes values from to . Therefore:This gives:

When . So plug these values into the equation using the values of and that we've just found:So the equation is of the form

, for any integer (This is using degrees - but you can write in radians if you like)

The only other option would be to eliminate , and express this in terms of and . Without more information, that's all you can say.

Grandad