Posted by greeny on .
the function is one of the form y=g(x) +cosbx. find two linear functions y1 and y2 related to g such that y1 is less than or equal to y is less than or equal to y2.
a. y= 2x + cos x
b. y= 10.5x+ cos2x

pprecalc 
Steve,
since 1 <= cosx <= 1
(a) 2x1 <= y <= 2x+1
(b) 1.05x1 <= y <= 1.05x+1
or, .05x <= y <= 2.05x
visit
http://rechneronline.de/functiongraphs/
and play around some to see