Answer:
a) Only the first one is an identity.
Step-by-step explanation:
1). 8 cos O tan O csc O = 8 simplifies to:
cos O tan O csc O = 1
cos O * (sin O / cos O) * (1 /sin O)
= cos O sin O / cos O sin O
= 1
So it is identity.
2) 13 sec^2 O/ cos^2 O - tan^2 O / cos^2O
= 13 sec^2 O - tan^2 O / cos^2 O
Now sec^2 O = 1 + tan^2 O, so we have:
(13( 1 + tan^2 O) - tan^2 O) / cos^2 O
= (12 tan^2 O + 13) / cos^2 O
This is not always = 2 so its not an identity.
