Inverse Trig Derivatives
Inverse trig functions (arcsin, arccos, arctan) have derivatives that involve square roots. These are worth memorizing for integration later.
Inverse Trig Derivatives
Inverse Trig with Chain Rule
Medium
Find d/dx[arctan(2x)]
1
Apply chain rule
= 1/(1+(2x)^2) * 2 = 2/(1+4x^2)
Answer:
2/(1+4x^2)
Practice
1. d/dx[arcsin(x)] = ?
Key Takeaways
arcsin and arccos have sqrt(1-x^2) in denominator
arctan has 1+x^2 in denominator
arccos is negative of arcsin
These formulas appear often in integration