# Math Help - Trig Function Equations

1. ## Trig Function Equations

1. (tan^-1)x = -1

2. sin^-1(sinx) = π/10

2. Originally Posted by live_laugh_luv27
1. (tan^-1)x = -1

2. sin^-1(sinx) = π/10

edit: Ok it seems this isn't enough to grab your attention. For #1) you can also think of it as $x=\tan^{-1}(-1)$. So if x is an angle, -1 is a ratio. That is obviously simplified though, since the ratio is of (opposite)/(adjacent). Thus must be that either the opposite leg is 1 or 1 and that the adjacent leg is 1 or -1, but they can't both be the same sign, or the ratio would be positive.