A reminder about inverse trigonometric functions
arcsin𝑥 
Sometimes written sin−1𝑥 
Range: −𝜋2,𝜋2 
Inverse function for sin𝑥 
arccos𝑥 
Sometimes written cos−1𝑥 
Range: 0,𝜋 
Inverse function for cos𝑥 
arctan𝑥 
Sometimes written tan−1𝑥 
Range: −𝜋2,𝜋2 
Inverse function for tan𝑥 