# A Trigonometrical Ratios

#### Sourav Guha

I have a mathematical term of the form tan(A.x)/tan(B.x)=C.How do I find out the value of x?

#### fresh_42

Mentor
2018 Award
I would try the addition theorem for sine, since you have $\sin(Ax) \cos(Bx) = C \sin(Bx) \cos(Cx)$. Or solve it numerically, e.g. by the help of WolframAlpha.com.

#### Sourav Guha

I would try the addition theorem for sine, since you have $\sin(Ax) \cos(Bx) = C \sin(Bx) \cos(Cx)$. Or solve it numerically, e.g. by the help of WolframAlpha.com.
By using Addition Theorem,I finally get sin(A+B)x=-sin(A-B)x..Now how do I find x?

#### fresh_42

Mentor
2018 Award
By using Addition Theorem,I finally get sin(A+B)x=-sin(A-B)x..Now how do I find x?
I wonder where the $C$ has gone. But if you have what you say, then we can use $-\sin(\alpha)=\sin(-\alpha)$ and then you can apply $\arcsin$.

"Trigonometrical Ratios"

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