identitas sec x sin x = tan x

secx sinx = tanx

--> secx sinx
= 1/cosx sinx
= sinx/cosx
= tanx

Semoga membantuu :)

Bab Trigonometri
Matematika SMA Kelas X

sec x . sin x
= (1/cos x) . sin x
= sin x / cos x
= tan x

terbukti