To solve equations involving inverse trig functions: (1) Isolate one inverse trig term if possible. (2) Use complementary identities to convert to a single type. (3) Apply the appropriate addition/subtraction formula. (4) Take the trig function of both sides to eliminate the inverse. (5) Solve the resulting algebraic equation. (6) VERIFY each solution satisfies the domain constraints of every inverse trig function in the original equation. Example: sin^(-1)(x) + cos^(-1)(2x) = pi/6. Rewrite cos^(-1)(2x) = pi/6 - sin^(-1)(x). Take cosine: 2x = cos(pi/6 - sin^(-1)(x)) = cos$\frac{pi}{6}$*sqrt(1-$x^2$) + sin$\frac{pi}{6}$*x. Solve the resulting algebraic equation and verify domain: -1 <= x <= 1 and -1 <= 2x <= 1, so x in [-1/2, 1/2].