tan (x+y) - tan y
---------------------
1+ tan(x+y) tan y
Thanks!
Very vaguely. I am taking an online course and it is difficult to learn without a book. Sometimes seeing it written out helps me to understand. Otherwise I have to scour the internet looking at examples and piecing things together. Last time I ever take an online class that is for sure
$\displaystyle tan(U-V) = \frac{tanU - tanV}{1 + tanUtanV}$
if you look at it closely it is similiar to the to the given formula
so that the U value is $\displaystyle (X+Y)$ and the $\displaystyle V$ value is $\displaystyle Y$
so then $\displaystyle tan(U-V)$ is $\displaystyle tan((X+Y) - Y)$
or just $\displaystyle tan(X)$
I have taken distance learning also, but with forums like this you get lots of help some times better than a class room