# Question #199ee

##### 1 Answer

Aug 7, 2017

Write the function as:

As

we can put:

so that:

with

Thus the function is a sinusoid of amplitude

increasing when:

and again decreasing for

It is concave up for:

and concave down in the rest of the interval.

graph{sqrt5cos(x+1.1071487178) [-0.1, 6.3, -3, 3]}