Jawabanmu

2014-01-03T20:37:31+07:00
1/(secx+cosecx) =sin 2x.
1=(1/cos x +1/sinx) 2 sinx.cosx

[(sinx+cosx)/sinxcosx] .2 sin xcosx=1.

Sin x+cos x=1/2.....(1)

(sinx+cosx)"=(1/2)"
1+2sinx.cosx=1/4.

Sinx.cosx=-3/8.....(2)

secx+cosecx=(sinx+cosx)/sinxcosx.=1/2(-8/3)=-4/3.