Question

if sin theta is equal to zero then sec theta is equal to dash

Answer 1

it will 1 because ...........

sinsquareq +cossquareq=1

then cosq=1 so secq =1

Answer 2

sec theta = 1/cos theta
now,
sin^2 theta +cos^2theta =1
given
sin theta =0
then,
cos^2theta=1
therefore
cos theta =1
so,
sec theta=1/cos theta
sec theta =1/1
hence,
sec theta =1