Equation of A+Bsinx or A+Bcos x From a Graph
\[y=A+B cos x, \: A+B sin x\]
, shown below, We can easily find \[A\]
and \[B\]
\[A=\frac{y_{MAX}+y_{MIN}}{2}=\frac{7+3}{2}=5\]
\[A=\frac{y_{MAX}-y_{MIN}}{2}=\frac{7-3}{2}=2\]
The equation of the graph is
\[y=5+2 cos x\]