For this case we have the following expression: tan 120º Rewriting we have: tan 120º = sine 120º / cosine 120º We can rewrite the expression based on an acute angle. We have then: tan 120º = sine 60º / - cosine 60º Rewriting we have: tan 120º = - tan 60º Answer: the function as 120º as a function of an acute angle is: A. - tan 60º
