Second-degree homogeneous equations

A second-degree homogeneous trigonometric equation has the form $A\sin^2 x + B\sin x\cos x + C\cos^2 x = 0$, in which all the monomials have the same total degree (two) in $\sin$ and $\cos$. It is solved by dividing by $\cos^2 x$ and obtaining a second-degree equation in $\tan x$. Equations with an additional constant term can also be reduced to this form.

• Definition and solution method
• Equations reducible to homogeneous ones