1. The problem statement, all variables and given/known data (e) What is the angle made by the velocity vector with the horizontal? A projectile is shot from the edge of a cliff h = 165 m above ground level with an initial speed of v0 = 145 m/s at an angle of 37.0° with the horizontal, as shown below: http://img135.imageshack.us/img135/3468/projectilelaunchox5.th.jpg [Broken]http://g.imageshack.us/thpix.php [Broken] Seconds in the air is 19.532760239244074174748994000901s Range of total distance traveled is 2261.9356107635250879761691838034m Final Velocity for x before it hits the ground: 115.80214895685746271118011659m/s Final Velocity for y before it hits the ground: -104.15787198754492632443347614472m/s (upwards is positive) Magnitude of final velocities (hypotenuse-more or less): 155.75300960174092250733936761367m/s These are just other informations obtained throughout the problem. 2. Relevant equations Trigonometry-sin/cos/tan 3. The attempt at a solution Basically I used opposite divided by adjacent and then inverse tan it. Tan θ = opp/adj Tan θ = 165m/2261.9356107635250879761691838034m θ = 4.172129598188136156302219438937° Here is a picture of it, very slightly modified: [img=http://img583.imageshack.us/img583/733/projectilelaunchangleik5.th.jpg] (the picture wont show up as image) This did not come out as correct. If anyone can point out errors to find the correct answer, it would be appreciated.