Can You Solve this Trig Inverse Equation with arctan and arctan?

  • Thread starter Thread starter JoshB645
  • Start date Start date
  • Tags Tags
    Inverse Trig
Click For Summary
SUMMARY

The equation arctan(3x) + arctan(2x) = π/4 can be solved using the identity arctan[x] + arctan[y] = arctan[(x+y)/(1-xy)]. By applying this identity, the equation simplifies to 5x/(1-6x²) = 1. The solutions yield x = 1/6 and x = -1, with x = -1 being rejected due to the domain restrictions of the arctan function.

PREREQUISITES
  • Understanding of trigonometric identities, specifically the arctan addition formula.
  • Knowledge of solving rational equations.
  • Familiarity with the properties and domain of the arctan function.
  • Basic algebraic manipulation skills.
NEXT STEPS
  • Study the derivation and applications of the arctan addition formula.
  • Learn about the domain and range of inverse trigonometric functions.
  • Practice solving rational equations involving trigonometric identities.
  • Explore other trigonometric identities and their proofs.
USEFUL FOR

Students studying trigonometry, educators teaching inverse trigonometric functions, and anyone looking to enhance their problem-solving skills in mathematics.

JoshB645
Messages
2
Reaction score
0

Homework Statement


Solve arctan 3x + arctan 2x= pie/4?


Homework Equations





The Attempt at a Solution

 
Physics news on Phys.org
there is a trig identiy that helps.

arctan[x]+arctan[y] = arctan[(x+y)/(1-xy)]

then it is just the angle that has a tan of pi/4 (i am assuming radians), so 1

then solving 5x/(1-6x^2)=1 we get x= 1/6 and x=-1
reject the -1 as the domain of arctan does not include it if is re-inserted into the fuction.
 

Similar threads

  • · Replies 17 ·
Replies
17
Views
4K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 15 ·
Replies
15
Views
2K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
Replies
2
Views
2K