[gregr507]

Hey guys I'm a junior and im in pre calc right now, I'm doing my homework but this one problem is stumping me for some reason. It's the type of problem where you have been given 2 sides and an angle of a triangle and you have to find the 2 possible triangles that have those 2 sides and the angle.

ANyway, the measure of angle B is 17 degrees, side b is 10, and side c is 19. I already found the solution for the first triangle, i think it is side a is 26.5, angle C is 33.7, and angle A is 129.3. But I'm having trouble finding the measurements of side a and angles C and A for the second triangle.

I feel dumb for not being able to get it, I've gotten all the other ones correct, but for some reason I'm spacing out on this one. Thanks for the help

 

[450]

Hmmm... Law of cosines... Law of sines...

Argh...I cant remember!


http://hyperphysics.phy-astr.gsu.edu/hbase/lcos.html

 

[mjg]

i took this message out, it was wrong sorry.

 

[zachary80]

Your first numbers are right.

Wouldn't you just need to do (180-C) to get C on the other triangle? Then you could work from there.

 

[gregr507]

That's what I was doing before zachary but when I plugged it into my calculator I must have typed something in wrong because before I used the law of sines and the two angles/sides didn't work, and now they do. Anyway I just worked from there and it all worked out fine. I feel like an idiot lol, oh well thanks for the help

 

[Beach123456]

Damn.

I have a feeling im goin to hate calculus. I cant make a word of sense out of any of what you said. Except the 180 degrees in a triangle thing.

(Im in algebra 1)

 

[bigben7]

I am taking Calculus 2

Its not that bad so far. I still have to take 2 more calculus. My instrutor said Cal 3 & 4 are nothing compared to Cal 2 because from Cal 3, we will be allowed to use Ti 89. Yes we have to pass Cal 2 without any Ti's... Sucks..

 

[gregr507]

I'm gonna take AP Calculus AB next year, I'm really not looking forward to it

 

[djgustashaw]

Quote:

I am taking Calculus 2 Its not that bad so far. I still have to take 2 more calculus. My instrutor said Cal 3 & 4 are nothing compared to Cal 2 because from Cal 3, we will be allowed to use Ti 89. Yes we have to pass Cal 2 without any Ti's... Sucks..

Wow man that sucks. I'm in calc 2 right now and I'm not enjoying Taylor Polynomials or LaGrange error. Hopefully we should start linear algebra soon, I hear matrices and such aren't nearly as bad. Luckily though, my professor makes our tests open book and notebook and we can use any calculator we want... all I have is a Ti-83 though

 

[MuZI]

Can you scan the problem?

Try to draw a visual in paint because then it would be easier to help.

 

[The Actual]

Quote:

Originally Posted by zachary80 Wouldn't you just need to do (180-C) to get C on the other triangle? Then you could work from there.

Do this, and then if the new C is less than 163 degrees (180-17), it means that there is another triangle to solve. Then use law of cosines (A=BC+2BCsin(angle A) or something. I don't remember right now) to solve the sides.

I did this in my precalculus class last semester. Just keep trying and if you are still having trouble try to talk to your teacher before or after class sometime.

 

[Hunterboy55]

Wow, I'm in precalc and we are nowhere near that point

 

[bigben7]

Quote:

Originally Posted by djgustashaw Wow man that sucks. I'm in calc 2 right now and I'm not enjoying Taylor Polynomials or LaGrange error. Hopefully we should start linear algebra soon, I hear matrices and such aren't nearly as bad. Luckily though, my professor makes our tests open book and notebook and we can use any calculator we want... all I have is a Ti-83 though

This is funny but I was allowed to use to Ti-83 in my pre cal class but not in Cal 1 or 2. You won't believe what my friend did in order to pass pre cal. We were not allowed to use Ti 89 because it can solve any problem in no time. So this kid changed the Ti 89 outer cover with a Ti 83's cover and literally used the Ti 89 throughtout the semester without getting caught. I am like damn that mother******( *hint for all the folks who are not allowed to use Ti-89 but can use Ti-83. Try to do it at your own risk. Its just like changing the amp case

*)
We are still doing different integration methods in our Cal 2 class. I hate Sequences & Series. I just can't figure out the difference between the two....

 

[mjg]

Before i fine tune what i mentioned:

Calc 3 is easier then calc 2... Hmmm... Calc 3 will build deeper on concepts learned in calc 1, like the theory behind calculus, and a bit more algebrical then the rule memorizing type of stuff calc 2 does.

Calc2 is the easiest. You learn how to evaluate an integral, then you learn
about series and sequence. This is stuff you commit to memory. You famailiarize yourself with a cut and dry process to answer a problem. Or i guess the conesus oft this thread is you learn how to input it into a calculator : / A ti 89 vs a ti 83 is mostly the interface, multivariate graphing, and really neat software that helps me as as computer science major as well as combinatorics stuff i do. It's not like having a ti89 is like having a major advantage in these sort of classes, actually it's a disadvantage if you find yourselves relying on it. Calc3 will go over some linear algebra topics, complex cordinate systems (vector spaces, gradient, geometry in 3rd dimension stuff). Spherical coordinate system etc. I found it alot harder then calc 1 or 2. Calc 4 is all differential equations, that is the b!tch of the bunch to most people.
It's only required for engineering and math majors, but it's an elective for AMS .

Oh yea,
Think of a sequence as a pattern. Like (-1)^X is
an alternating sequence, it isn't converging towards a particular value, and it's sum will be zero at any point.

Yet, a series, a convergant one, approaches a certain value. You will use the Sigma to evaluate it term by term, but let it collapse into an algebraic sum.
It's a recursively defined idea, broken into pieces, or discretely represented by a form you will learn for the series.

anyways...

law of sines says that in any triangle the lengths of the sides are proportional to the sines of the correspinding opposite angles.
A

c b


B a C

capital are angles, lower case sides.


so SinA/a = sinB/b = sinC/c

 

[tennisets]

Quote:

Originally Posted by gregr507 I'm gonna take AP Calculus AB next year, I'm really not looking forward to it

I'm taking BC calc right now (I guess that would be Calc 2 this semester, we're doing sequences and series with integral calculus). You have no idea of the amazing stuff you will learn in calculus. I thought precal was pretty boring too, but when I started calc in the spring of my junior year, I loved it (that would be A calc). Just stick with it, and make sure you talk to the teacher if you don't understand something. I'm lucky in that my teacher is my favorite teacher in the school and my advisor. Oh, I guess it also helps that my calculus class only has 11 students in it. I go to a private school so the biggest class I have ever had was 16 students.