Anyone here good at math?

[Camshaft Ramrod]

mmmmm Trig. That's what I'm doing now. To be honest, as soon as I saw sin, cos, and what not, in your Q, I stopped reading it. I spend hours a day studying and doing homework for that stupid class. Don't wanna confuse my brain.

Our teacher didn't really worry too much about bearings this semester. Where are ya going to school?

 

[Knowdafish]

Not a hard question. Just draw a triangle relative to the information given and fill in the blanks! 4 hours?

 

[snakeguy101]

Not a hard question. Just draw a triangle relative to the information given and fill in the blanks! 4 hours?

I did that but the answer I was getting for the angles was wrong. I didn't realize it was a reference angle so I spent an hour double checking my math and then the formula and when that didn't work, I called some friends that are good with math when none of them were able to help, I turned to the internet and scoured a dozen math help forums. When that didn't work, I went back to the text book and when that didn't work, I youtubed it on a whim. It worked, I was able to find a video of a person working a similar problem and follow their steps.

 

[makoshoemaker]

I need help with the following trig problem and my tutor is out of town and out of touch...

A boat leaves a port and travels due east. From the port, there is an island 45.2 miles away on a bearing of 65.0º. After a boat has traveled 31.2 miles, find the bearing angle of the island from the boat. All bearing angles measures clockwise from due north.

here is what I have so far:
using the law of cosines, a^2=45.2^2 + 31.2^2- 2(45.2*31.2)cos(25), a=21.45
Then using the law of sines, I get (sinB/45.2)=(sin25/21.45)
SinB=.89055... Sin(^-1)(.89055)=B=62.9º

but B≠62.9º since it must be an obtuse angle in order to fit this application.

A=25º, a=21.45mi
B= 62.9º? b=45.2mi
C=92.1? c=31.2mi

Thanks in advance for your help. I know this is not really the place to look but I figured it is worth a shot.

What class is this?

 

[snakeguy101]

What class is this?

Trig

 

[Juxtaroberto]

Not a hard question. Just draw a triangle relative to the information given and fill in the blanks! 4 hours?

I did that too. I've got a spare piece of paper with a little square as the dock, a big arrow pointing up labeled N, a big arrow pointing to the right labeled E, and off to the side an amorphous blob that's supposed to be the island. I brushed up on the laws of cosine and sine, and I got the same answer he was getting, except he'd said it wasn't the right answer. I think we were just solving for the wrong angle.

 

[Otolith]

(SOLVE......,x) XD only way I made it through all those type classes with my sanity. Good investment if you still have some calc or physics left.

 

[snakeguy101]

Okay, I turned in the paper and I got it correct. The problem is that the law of sines will only solve for quadrant I angles and I should have been using the law of cosines to solve for an obtuse angle. What I did was solve for the supplementary angle of the triangle and not the actual angle that I was looking for.