Solving definte integral

[shortman12012]

So i just started learning about how to solve definite integrals and this problem is the last one on my homework. I just need to know how to start it, cause I'm completely lost on how it would start, any hint would be helpful

 

[tkhunny]

Have you forgotten your algebra?

I'm tempted to expand the binomial-looking-thing and treat each of the three pieces separately. The first two should be easy. The sine-squared might require a half-angle identity at worst.

Let's see what you get.

 

[shortman12012]

okay so if i expand it out then i would get
(5-3sin(ɵ))(5-3sin(ɵ))
25-15sin(ɵ)-15sin(ɵ)-9sin^2(ɵ)
25+9sin^2(ɵ)
25+9(1/2-1/2cos(2ɵ)
25+9/2-9/2cos(2ɵ)
59/2-9/2cos(2ɵ)

okay so this is what i have so far, is there any mistakes or more simplifying i can do before i go ahead and integrate?[h=1][/h]

 

[tkhunny]

-15-15 is NOT zero (0).

Posting the same problem and the same careless solution in multiple locations wastes the time of volunteers. Don't do that.

 

[shortman12012]

 

[tkhunny]

Well, sure, but this is clearly not your work. This is one of the difficulties with multiple postings. Posting someone else's answer from one board onto a different board just isn't helpful.

Good luck in your endeavors. When you really want to work and learn, let's see on what else you are working.