Inverse Trignometric Functions
sin (sin-1(1/5) + cos-1(x)) = 1
(sin-1(1/5) + cos-1(x)) = sin-1(1)
sin-1(1/5) + cos-1(x) = /2
Now by using the property,
sin-1(x) + cos-1(x) = /2
⇒ x = 1/5
Similarly try the second question.
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