Solve `e^(sin x)-e^(-sin x) - 4 = 0`.

1.	Solve `e^(sin x)-e^(-sin x) - 4 = 0`.
Answer» Given that ` e^(sin x) - e^(-sin x) - 4 = 0`. Let ` e^(sin x) = y`. Then, given equation becomes ` y-1/y - 4 = 0` ` or y^(2) - 4y-1 = 0` `:. Y = e^(sin x) = 2 + sqrt5, 2- sqrt5` Since ` e^(sin x) gt 0, e^(sin x) ne 2 - sqrt5` Also, maximum value of ` e^(sin x )` is e when sin x = `. So, ` e^(sin x) ne 2+ sqrt5` Therefore, given equation has no solution.

Discussion