The magnetic field at the axis of a long half cylinder if current is 6A and 2m be the radius.

I know it's bit easy but still I am having a problem.

I thought the hollow long cylinder as a cluster of thin wires along its surface assuming

a d$\theta$ element and $\theta$ being angle with horizontal I realise that on cos component will come in my equation as the sin component is being cancelled.

dB = $(\mu_0/4\pi)\frac{2.6.d\theta}{2}$

Now what ? Should I integrate it with limits 0 to $\pi$