The correct option is C sin−1(2sinx−1)+c
Let, √1+cosec x=t=>−cosec x cot x2√1+cosec xdx=dtsin x
=1(t2−1) and cos x=√1−(1(t2−1))2=t√t2−2t2−1
Substituting back,
=∫−2tdt(t2−1)√t2−2
Let, t2−2=m=>2tdt=dm
Substituting back,
∫−dm(m+1)√m
Let, m=p2=>dm=2pdp
Substituting back,
=∫−2pdp(p2+1)p
=∫−2dp(p2+1)
=−2tan−1p+c=−2sin−1p√p2+1+c
=−2sin−1√t2−2t2−1+c
=−2sin−1√1−sinx+c