Answer:
The first one, the third one, and the fourth one
Step-by-step explanation:
The 1st one is the Pythagorean identity. One of the most essential trig identities you have to remember.
The second one is false because A is equal to 60 and b is equal to 30 and the left side turns into 0.5 while the other side becomes -0.5.
The third one is true since it is a distinction of the identity [tex]tan^2+1[/tex] = [tex]sec^2[/tex] (OR you can simply just subtract [tex]tan^2[/tex] from either side).
The fourth one is true since it's just a different version of [tex]1+tan^2=sec^2[/tex].
