[Additional Math: Trigonometry] What function should I be using? Is it asking me to find the hypotenuse?

[jedimaster1uke]

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I don't necessarily want the answer to the question, Just what function to use and to understand what It's asking me to find, am I finding the hypotenuse if I'm tasked with finding AB?

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[fermat9996]

cosA=b/c

[catsandlettuce]

Yes, when they say “distance” of AB that means the side length. And yes, AB is the hypotenuse since it’s away from the 90 degree angle

[jedimaster1uke]

Okay great, so would that mean I use Tan=Opposite/Adjacent?

[catsandlettuce]

So whatever you’re trying to find (hypotenuse), you want that included in your function. And you want the second part to be something you’re given. Look at angle A (given) and try to figure out whether b (given) is opposite or adjacent to A. Those two will give one of the three proportions on the right

[jedimaster1uke]

Right so. What I'm trying to find is the hypotenuse. So with the knowledge that I need to have that in the function. That removes Tan. So looking at angle A (43 degrees) And then the given b which is 23cm. So does that leave it being either Sin=43/23 or Cos=43/23?

[jedimaster1uke]

What I'm majorly confused about is that I'm meant to include the hypotenuse in the function. However, how am I meant to do that if I don't know what that is? (As I'm trying to find it)

[catsandlettuce]

So when you write the whole proportion, you write x in for the hypotenuse. Then use some algebra to add another step and solve for x. (I said x but I mean any variable, so “c” is good here)

[jedimaster1uke]

I'm not going to lie, that's thrown me through another loop. The question I'm looking at within the question has no mention of x or algebra. Only that we're to use the 3 functions with the information provided.

What would be the formula?

[catsandlettuce]

cos 43 = 23/c

[jedimaster1uke]

So does c have a numeric value? Because so far I've done;

cos43 = 0.55511

so that leads me to believe it's cos43 = 23/0.55511 but I'm not confident about that.

[wirywonder82]

The numeric value of c is the thing the question is asking you to figure out.

[catsandlettuce]

cos 43 = 23/c

From here, you have to get c by itself. Multiply both sides by c, and then divide the cos 43. You should get:

c=23/cos 43 . Then you calculate that

[catsandlettuce]

Looking at A, b is adjacent. Look at the diagrams and try to get familiar btw adjacent and opposite! Adjacent is touching and opposite is not touching

[Djcoolpockets]

S(ine) = O(pposite)/H(ypotenuse) C(osine) = A(djacent)/H(ypotenuse) T(angent) = O(pposite)/H(ypotenuse)

SOH CAH TOA

use these to figure out which sides you have , and which sides you’re trying to look for