2. Relevant equations x*cos(Ax) + B*sin(Ax) = 0 Where A and B are nonzero constants. 3. The attempt at a solution The only value of x where both terms are zero is x=0. All other solutions (presumably an infinite number of them) occur when: x*cos(Ax) = -B*sin(Ax), x≠0. This seems intractable to me, but I don't have the math skills required to recognize an equation that cannot be solved algebraically.