Trigonometry maths help

[yoda]

it's been 13 years since i last used trig (at school) and my memory isn't that wonderfull...

basically, i' trying to work out direction of travel when i know my curent long and lat position and i know the long and lat of where i'm trying to go...

the formula i found sofar is...

TAN a = longitude diference / latitude diference

so, for example... if the longitude diference is 50 and latitude diference is also 50 then the tangent of the angle is 1...

How do i then work out what the angle is from the tangent?

Thanks

 

[yoda]

well done... i allready knew that... i'm after how to convert it... whats the formula to work it out...

I picked 50 by 50 coz it's odvious the answer should be 45...