How Do You Integrate cos[(pi/9)(x^2)]?

[jmrec100]

Homework Statement

Integrate cos[(pi/9)(x^2)

Homework Equations

Is there a trig identity for the cos(x^2) ?

The Attempt at a Solution

U=(pi/9)T^2
dU= [2(pi)/9] (T)dT dT= dU/ {[2(pi)/9 (T)]}

Substitute in get cosU dU/ {[2(pi)/9 (T)]} Now what?

 

[gabbagabbahey]

Homework Statement

Integrate cos[(pi/9)(x^2)

Do you mean:

\int \cos\left(\frac{\pi x^2}{9}\right)dx[/itex] <br /> <br /> or something else? Are you given integration limits, or are you only asked for the indefinite integral?