Is there any way of integrating this trigonometric function $$\int \cos(x^2)dx$$ ? Wolfram alpha straight away gives this $$\sqrt{\frac{\pi }{2}}C\left ( \sqrt{\frac{2}{\pi }} x\right )+\text{constant}$$ without showing any steps.
It would be very helpful if someone could show the steps for me please..
Thank You