Question

Write the expression as either the sine, cosine, or tangent of a single angle.

sine of pi divided by two times cosine of pi divided by seven plus cosine of pi divided by two times sine of pi divided by seven.

Answer 1

\[\sin \frac{ \pi }{ 2 }\cos \frac{ \pi }{ 7} + \cos \frac{ \pi }{ 2 }\sin \frac{ \pi }{ 7 }\]

Answer 2

http://www.sosmath.com/trig/addform/img1.gif <--- notice the 3rd identity

\(\bf \sin \frac{ \pi }{ 2 }\cos \frac{ \pi }{ 7} + \cos \frac{ \pi }{ 2 }\sin \frac{ \pi }{ 7 }\implies sin\left(\frac{ \pi }{ 2 }+\frac{ \pi }{ 7}\right)\)

Answer 3

@jdoe0001 Thank you so much! that makes alot of sense to me now!