SOH CAH TOA these are all the relations we've learned within trig and I tried them on this question using the angle they give me but I cant get the right awnser. The awsner is 7.6 cm in the back of the book but I dont get that when I try it. Heres a quick paint sketch of the problem in the text book. Anyone know how to get 7.6? we just started this stuff today.

You need COS, which is adjacent over hypotenuse.

So, your equation is COS(54) = 13/x

Give or take some rounding and you have 7.6

You may have been using SIN or TAN, or your calculator is set to something other than degree mode. If its set to calculate in radians then you're gonna get the wrong answer.

This is what I tried first, it must be my calculator or somthing because I get 22.14 when I do that. I go COS(54) = 13/x
0.587/x = 13/x
0.587x = 13
0.587/0.587 13/0.587
x=22.14 (when it should be 7.6)
Am I doing somthing wrong?

after you get to .587/x = 13, your statement that .587x=13 is wrong.

you need to multiply 13 by .587 to get X.

ok so I just find COS(54) then do the divison then multiply?

and if so is that the way to do it for all problems looking like this using COS?

follow this logic:

Cos(54) = 13/x

.587 = 13/x

multiply both sides by x, and you get

.587x = 13

call .587 y and follow this logic

xy = 13

therefore, 13y = x

if we know y to be .587, that means 13(.587) = x = approx 7.6

Oh ya ya in my 2nd last post I meant cross multiply. Thanks for the help, it probly would've taken me much longer to figure that out on my own.

Yeah its best to just ask sometimes, this is all stuff you've been taught and know, but sometimes the basic rules of multiplication and division just leave us for a few seconds

I am definitely stupid on math...

I've always hated math myself.

Somehow I fell into a career that uses it everyday [:@]

I find it helps to write SOH CAH TOA in large bold letters at the top of the page. I'm in college and I still do that.

...

Sweet, 3-4-5 triangle!!

Sine: O/H
Cosine: A/H
Tangent: O/A

Oscar Had A Hold Of Arthur (Oscar the grouch, and Arthur the Aardvark)

thats how i remember...hehe

or you could just use SOHCAHTOA. Im thinking about turning this into an official math thread, what do you guys think?

Seems like a fair idea, I don't see many math related threads but I'm sure many people here are taking math classes of various levels and it would be cool to have a general help area.

Some old hippie caught another hippie trippin' on acid.

Anyone wanna help me with synthetic devision? Pre-calc stuff..? Yea I was abscent for a little while so anyone wanna help me out?

make sure your calculator is set on degress not radians when your finding the angles using trig. that messes me up sometimes.

Man, you guys are allowed to use calculators......

Wish I could, I dont get into calc until at least grade 11, mabey grade 10.

I am sure if the problem is posted, someone here might be able to help... (probably not me, but someone would!!)

Ok lets give it a try..This isn't just synthetic division tho.. it uses it but its not only synthetic division.

Find all zero's of each of the following polynomials.

f(x)=6x^3 - x^2 - 13x +8

thats easy if you can use a graphing calc. Type the equation into and then go to graph. You know there is 3 zeros because the highest x power is to the 3rd. After you put it in go to the calc button above the trace key and select zeros. Then set the left boundary and right. The boundries will be the two sides of the line where it crosses the x axis.

so they are:
X=-1.644243
x=.81090999
x=1
For that equation the zoom box helps alot to get close in on it.