Find the value of 2.arccos 3/√13 + arccot 16/63 + arccos 7/25
Answer: arctan 3/4
How to solve this?
Hello,
I've seen some problems solved this way, but I just can't do them...
I'll try, but MY way, that is to say : calculations !
Here are the formula I'll use :
(formula 18 : Inverse Tangent -- from Wolfram MathWorld)
(formula 12 : Inverse Cosine -- from Wolfram MathWorld)
(formula 36 : Inverse Tangent -- from Wolfram MathWorld)
Using formula (1), we have to solve :
Using formula (2) and after some simplifications, we have to solve :
Using formula (3), we get :
Using formula (3) once again, we get :
And I must say I'm lost here...