Q.

Let the inverse trigonometric functions take principal values. The number of real solutions of the equation 2sin-1x+3cos-1x=2π5, is _____.    [2024]


Ans.

(0)

We have, 2sin-1x+3cos-1x=2π5

2(π2-cos-1x)+3cos-1x=2π5

π+cos-1x=2π5  cos-1x=-3π5

Which is not possible as cos-1x[0,π]

No solution exists.