Core 3 - integration by parts

Right so I'm stuck on this problem and the answer is apparently 0.25 but I don't end up with anything near it so here we go.

$\int^\frac{\pi}{4}_0\ xsin2x\ dx$

So I have integrated by parts and I obtain:

$\frac{sin2x}{4} - \frac{xcos2x}{2}\ + c\$

I then end up with;



This is worth five marks. So yeah, any help?

You've integrated by parts correctly but made a mistake in subbing in your limits - In fact, I can't even decipher what you've done with subbing in your limits so you may need to post a bit more working on that part. Also, in definite integration (i.e. integration between limits), the arbitrary constant doesn't affect the result so you can omit the +c.

Right so I'm stuck on this problem and the answer is apparently 0.25 but I don't end up with anything near it so here we go.

$\int^\frac{\pi}{4}_0\ xsin2x\ dx$

So I have integrated by parts and I obtain:

$\frac{sin2x}{4} - \frac{xcos2x}{2}\ + c\$

I then end up with;



This is worth five marks. So yeah, any help?

Right so I'm stuck on this problem and the answer is apparently 0.25 but I don't end up with anything near it so here we go.

$\int^\frac{\pi}{4}_0\ xsin2x\ dx$

So I have integrated by parts and I obtain:

$\frac{sin2x}{4} - \frac{xcos2x}{2}\ + c\$

I then end up with;



This is worth five marks. So yeah, any help?

Right so I'm stuck on this problem and the answer is apparently 0.25 but I don't end up with anything near it so here we go.

$\int^\frac{\pi}{4}_0\ xsin2x\ dx$

So I have integrated by parts and I obtain:

$\frac{sin2x}{4} - \frac{xcos2x}{2}\ + c\$

I then end up with;



This is worth five marks. So yeah, any help?