JEE Main2012MathematicsTrigonometric EquationsActual
The equation e^ x -e^ - x -4=0 has
Options
- Ainfinite number of real roots
- Bno real roots
- Cexactly one real root
- Dexactly four real roots
Correct answer
B. no real roots
Step-by-step solution
e^ x -e^ - x =4 e^ x =tt- 1 t =4 array ll t^2-4 t-1=0 & t= 4 16+4 2 t= 4 2 5 2 & t=2 5 array e^ x =2 5 -1 x 1 1 e e^ x ee^ x =2+ 5 not possible e^ x =2- 5 not possible hence no solution