h(x) = x+cos(ax) is a family of functions where a is a positive constant such that 0<a<4. Which values of a make h(x) strictly decreasing? Justify your answer.

Question

I can't figure this out and help would be appreciated. Thanks in advance!

Answer 1

something wrong with Reiny's solution? See

http://www.jiskha.com/display.cgi?id=1430504193