If [sin–1 cos–1 sin–1 tan–1 θ ] = 1, where [.] denotes the greatest integer function, the θ lies in the interval
[tan sin cos1, sin tan cos sin1]
[sin tan cos1, tan sin cos sin1]
[tan sin cos1, tan sin cos sin1]
none of these.
We have, sin−1cos−1sin−1tan−1θ=1
⇒1≤sin−1cos−1sin−1tan−1θ≤π2⇒sin1≤cos−1sin−1tan−1θ≤1⇒cossin1≥sin−1tan−1θ≥cos1⇒sincossin1≥tan−1θ≥sincos1⇒tansincossin1≥θ≥tansincos1