Use the given function value(s),and trigonometric identities (including the cofunction identities),to find the indicated trigonometric functions.
sin 90° = 1,tan 90° = Not defined
Sin 0° and tan 0°

A)sin 0° = 0 and tan 0° = 0
B)sin 0° = 1 and tan 0° = 1
C)sin 0° = Not defined and tan 0° = Not defined
D)sin 0° = Not defined and tan 0° = 1
E)sin 0° = 1 and tan 0° = Not defined

Question

Use the given function value(s),and trigonometric identities (including the cofunction identities),to find the indicated trigonometric functions. ​
​sin 90° = 1,tan 90° = Not defined
Sin 0° and tan 0°
​
A)​sin 0° = 0 and tan 0° = 0
B)sin 0° = 1 and tan 0° = 1
C)​sin 0° = Not defined and tan 0° = Not defined
D)​sin 0° = Not defined and tan 0° = 1
E)​sin 0° = 1 and tan 0° = Not defined

Quizplus · Accepted Answer

Using the cofunction identity, we know that sin 0° = cos 90° = 0. 
Also, tan 0° = sin 0°/cos 0° = 0/1 = 0. Therefore, the correct choice is A).

Use the Given Function Value(s),and Trigonometric Identities (Including the Cofunction