Answer each of the following questions in one word or one sentence or as per exact requirement of the question:

If , find the value of x.


Given cos (sin-1 2/5 + cos-1 x) = 0


cos (sin-1 2/5 + cos-1 x) = cos (π/2)


sin-1 2/5 + cos-1 x = π/2


We know that sin-1 x + cos-1 x = π/2


x = 2/5


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