I have no clue what to do with Trigonometry

[Carson Steele]

I have been failing some tests on trig and one question was sinx=cos48. I have no clue what it means, please help

 

[Janus]

It's basically asking what value of x, if you take its sin, gives you the same answer as when you take the cos of 48.

 

[Carson Steele]

It's basically asking what value of x, if you take its sin, gives you the same answer as when you take the cos of 48.

Thanks for replying but you are still taking gibberish to me

 

[mathman]

Let a=cos48. Let sinx=a, find x. Also sinx=cos(90-x). 90-x=48, find x.

 

[jedishrfu]

There are some good short video tutorials at mathispower4u.com on trigonometry.

I would suggest working through them one by one doing the problems they do as they do it.

http://www.mathispower4u.com/trigonometry.php

 

[symbolipoint]

Studying Physics may help to make Trigonometry seem sensible. Basically, the trigonometric functions are cyclic functions, based on reference to circles and triangles. One needs to learn to make diagrams and draw and label figures.

 

[Demystifier]

Thanks for replying but you are still taking gibberish to me

Try
http://www.adelaide.edu.au/mathslearning/handouts/introtrigRevision.pdf
If this is gibberish too, then I give up.

 

[Nidum]

Try
http://www.adelaide.edu.au/mathslearning/handouts/introtrigRevision.pdf

+1

 

[Logical Dog]

Do you know what a set, element of a set, ordered pair? function? the definition of a functions domain, co -domain, image? functions defined as ordered pairs...variables like x y z are generic letters that stand for any element of a larger set:

https://en.wikipedia.org/wiki/Domain_of_discourse

https://en.wikipedia.org/wiki/Domain_of_a_function
https://en.wikipedia.org/wiki/Codomain
https://en.wikipedia.org/wiki/Range_(mathematics)

http://www.dummies.com/education/math/pre-algebra/evaluate-mathematical-expressions/
the whole sentence you posted there is called a mathematical expression, a mix of letters and symbols. The equal symbol is a mathematical relation, it states that two mathematical objects when evaluated, are equal.

So sin x = cos 48 means what is the number that can replace x so that the value of the sine of that number is equal to the number that is evaluated when we put cos 48.
As for what the sin, cos, tan functions you might want to read this:

https://en.wikipedia.org/wiki/Trigonometric_functions

for a basic introduction to set theory and functions as ordered pairs and relations you can check this page:
http://www.people.vcu.edu/~rhammack/BookOfProof/

also this page might help:http://www.mathcentre.ac.uk/students/topics/

 

[gleem]

What is the meaning of sin(x). draw a triangle with a unit length hypotenuse to represent x. What does sin(x) represent in your triangle. . Now repeat with a different triangle for another angle y. What does cos(y) represent in this triangle?

Now if sin(x) = cos(y) orient the triangles so that they are opposite one another. I there anything you can say about the relationship of x to y?

 

[vela]

I have been failing some tests on trig and one question was sinx=cos48. I have no clue what it means, please help

What are you doing taking trig if you don't know basic mathematics?

 

[symbolipoint]

What are you doing taking trig if you don't know basic mathematics?

Maybe the wrong understanding. Maybe Carson Steele went through Algebra 2, but many parts of Trigonometry don't make sense to him; they are too much for him but WE do not know why. MAYBE he needs to go through one or two of his earlier courses again, so that he might learn them better, and be well prepared to handle learning Trigonometry.

 

[gleem]

The question that he had a problem with has nothing to do with algebra. He was not paying attention in class or did not read the text. It is about the relationship between two trigonometric quantities. The sine of an angle is equal to the cosine of its complement for a right triangle.

 

[vela]

Maybe the wrong understanding. Maybe Carson Steele went through Algebra 2, but many parts of Trigonometry don't make sense to him; they are too much for him but WE do not know why. MAYBE he needs to go through one or two of his earlier courses again, so that he might learn them better, and be well prepared to handle learning Trigonometry.

I don't know. It seems a bit extreme to have "no clue what it means." That's quite different than simply not knowing how to solve the problem.

 

[Logical Dog]

Op you could also read pre math and algebra for dummies, its a great book and even I go back to it from time to time. Mark Z is a great author and i like all his books on math and logic.

Mark Zegarelli - basic math and pre algebra for dummies. Its hard to help you without an understanding of your background, this unfortunately entails a general knowledge of the landscape of matheamtics.

 

[Demystifier]

Do you know what a set, element of a set, ordered pair? function? the definition of a functions domain, co -domain, image? functions defined as ordered pairs...variables like x y z are generic letters that stand for any element of a larger set:

https://en.wikipedia.org/wiki/Domain_of_discourse

https://en.wikipedia.org/wiki/Domain_of_a_function
https://en.wikipedia.org/wiki/Codomain
https://en.wikipedia.org/wiki/Range_(mathematics)

http://www.dummies.com/education/math/pre-algebra/evaluate-mathematical-expressions/
the whole sentence you posted there is called a mathematical expression, a mix of letters and symbols. The equal symbol is a mathematical relation, it states that two mathematical objects when evaluated, are equal.

So sin x = cos 48 means what is the number that can replace x so that the value of the sine of that number is equal to the number that is evaluated when we put cos 48.
As for what the sin, cos, tan functions you might want to read this:

https://en.wikipedia.org/wiki/Trigonometric_functions

for a basic introduction to set theory and functions as ordered pairs and relations you can check this page:
http://www.people.vcu.edu/~rhammack/BookOfProof/

also this page might help:http://www.mathcentre.ac.uk/students/topics/

You are joking, right? Or do you really think that it could help someone who thinks that a statement in post #3 is a gibberish? I wouldn't be too surprised if he even didn't know what to do with 90-x=48 in post #4.

Or maybe he should first read Principia Mathematica by Whitehead and my avatar to see the proof that 1+1=2?

 

[symbolipoint]

You are joking, right? Or do you really think that it could help someone who thinks that a statement in post #3 is a gibberish? I wouldn't be too surprised if he even didn't know what to do with 90-x=48 in post #4.

Or maybe he should first read Principia Mathematica by Whitehead and my avatar to see the proof that 1+1=2?

Look at what I said back in post #12. Maybe the member did pass Algebra 1 and Algebra 2, but things just are not working for him in his try to learn Trigonometry. The Algebras are a different subject than Trigonometry. The combination of Geometry and cyclic functions may be too much for him right now, and in fact, he MAY NEED TO THOROUGHLY RESTUDY SOMETHING FROM PREVIOUS COURSES. Has a student ever been given a grade higher than he deserved, enrolled in the next course, and done badly?

 

[Logical Dog]

You are joking, right? Or do you really think that it could help someone who thinks that a statement in post #3 is a gibberish? I wouldn't be too surprised if he even didn't know what to do with 90-x=48 in post #4.

Or maybe he should first read Principia Mathematica by Whitehead and my avatar to see the proof that 1+1=2?

hahahahahahah xD...unfortunately I was quite serious

editL in all seriousness people need to know these things, they are basic, along with peano axioms. I guess its just up to the level where you can apply them effectively, but i want to learn it for the sake of it.

 

[stevendaryl]

I have been failing some tests on trig and one question was sinx=cos48. I have no clue what it means, please help

Well, if you try $x=42^o$, then you can demonstrate by using your calculator that:

$sin(42^o) = cos(48^o)$

Try it! So notice that if you start with

$sin(x) = cos(48^o)$

and replace $x$ by $42^o$, then you get a true statement. That's what it means to "solve" an equation such as $sin(x) = cos(48^o)$; it means find a substitution for $x$ that makes the equation true.

 

[Demystifier]

in all seriousness people need to know these things, they are basic, along with peano axioms. I guess its just up to the level where you can apply them effectively, but i want to learn it for the sake of it.

I also want to learn it for the sake of it, but OP just wants to pass the trigonometry exam. And obviously, his level in math is very low.

By the way, in the first year of elementary school we were taught sets before we were taught counting 1,2,...,10. It was a very modern approach to teaching mathematics at that time.

 

[Logical Dog]

I also want to learn it for the sake of it, but OP just wants to pass the trigonometry exam. And obviously, his level in math is very low.

By the way, in the first year of elementary school we were taught sets before we were taught counting 1,2,...,10. It was a very modern approach to teaching mathematics at that time.

the reality is whether for self fullfilment or for achieving anything useful, one has to learn it. There is no choice especially in the field of science. I believe in this time and after, No human will ever accomplish anything useful without having used some mathematics or some object born out of the use or relying on the principles of mathematics...for the most part.

I had no choice, but luckily I loved debating and combining old information to derive new, and argument structure and logic are crucial in mathematics. So I got lucky there.

 

[Demystifier]

No human will ever accomplish anything useful without having used some mathematics or some object born out of the use or relying on the principles of mathematics.

Sure, even your avatar dog uses a laptop, and the laptop relies on the principles of mathematics. But it doesn't mean that the dog himself knows any mathematics. Similarly, people who (for instance) use facebook can do many useful things with it. But it doesn't mean that they must know any mathematics to use facebook, despite the fact that facebook relies on the principles of mathematics.

 

[Logical Dog]

Sure, even your avatar dog uses a laptop,

Yes, and that dog is me. Whats your point?

But it doesn't mean that the dog himself knows any mathematics.

I tought i knew a little

Similarly, people who (for instance) use facebook can do many useful things with it. But it doesn't mean that they must know any mathematics to use facebook, despite the fact that facebook relies on the principles of mathematics.

agree but even basics like addition subtraction, multiplication division, the decimal system, should not be taken for granted.

 

[Demystifier]

Yes, and that dog is me. Whats your point?

A logical dog would not ask such an obvious question. This proves that your dog is more logical than you.

 

[Logical Dog]

A logical dog would not ask such an obvious question. This proves that your dog is more logical than you.

But we are both the same thing, dog = me. No evil xy variables in this expression!

 

[Demystifier]

But we are both the same thing, dog = me.

So you are an inconsistent system, which is good for your mathematician career because then you can prove anything.

 

[Logical Dog]

So you are an inconsistent system, which is good for your mathematician career because then you can prove anything.

sorry but you are speaking total gibberish now, the proof that I am a dog is too large to contain in one post. Good day.

 

[Demystifier]

the proof that I am a dog is too small to contain in one post.

Yeah right, Fermat also had a similar claim about one of his proofs. It turned out to be one of the most difficult proofs ever.

 

[Mark44]

This is post #29 and the last appearance of the OP was post #3. Let's hold off on further off-topic comments until the OP returns.