Perform the Indicated Operations and Simplify the Result So There $$\cos 67 ^ { \circ } = \cos 13 ^ { \circ } \cos 54 ^ { \circ } - \sin 13 ^ { \circ } \sin 54 ^ { \circ }$$

Q304: Rewrite the following as a product

Q305: Solve the problem.<br>-Find <span class="ql-formula"

Q306: Determine all solutions of the equation

Q307: Use a sum or difference identity

Q308: Use the fundamental identities to simplify

Q310: Write the product as a sum

Q311: Use the fundamental identities to find

Q312: Use a sum or difference identity

Q313: Use a sum or difference identity

Q314: Complete the sentence so the result