Verified answer

you mean simplify

we know if a +b = 90

let tan a = x and then cot b = x so tan b = 1/x

now b = 90- a = 90 - tan ^-1(x)

but b = arctan (1/x) so 90 - tan ^-1(x) = tan ^-1(1/x)

**** this was our topic in trigonometry. It's been a month since i last taken the exam like that. I forgot how to and even dont know how to solve that either ahaha. Sorry for not helping.

tan⁻¹(x) = π/2

=> x = tan(π/2) => undefined.

:)>