# Help, Math Pre-Trig

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Help me solve this please and explain it somewhat!

2 sin x = - 2 sin x + 3

so

sin x = 3 / 5

How do I solve this?

No calculator ps

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Note to everyone: Don't answer this question for him. But you can push him in the right direction.

The Doctor: There was a goblin, or a trickster, or a warrior... A nameless, terrible thing, soaked in the blood of a billion galaxies. The most feared being in all the cosmos. And nothing could stop it, or hold it, or reason with it. One day it would just drop out of the sky and tear down your world.
Amy: But how did it end up in there?
The Doctor: You know fairy tales. A good wizard tricked it.
River Song: I hate good wizards in fairy tales; they always turn out to be him.

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Ok, I've looked, and those two equations cannot go together.

2 sin x = - 2 sin x + 3

Add "2 sin x" to both sides.

4 sin x = 3

Divide both sides by 4.

sin x = 3/4

But the other equation says sin x = 3/5. It can't equal both.

The Doctor: There was a goblin, or a trickster, or a warrior... A nameless, terrible thing, soaked in the blood of a billion galaxies. The most feared being in all the cosmos. And nothing could stop it, or hold it, or reason with it. One day it would just drop out of the sky and tear down your world.
Amy: But how did it end up in there?
The Doctor: You know fairy tales. A good wizard tricked it.
River Song: I hate good wizards in fairy tales; they always turn out to be him.

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shoot was a mis type.

its

3 sin x = - 2 sin x + 3

so

sin x = 3 / 5

How do I solve this?

sorry, urg this sucks.

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I think you can guess by what I posted above. :-) Same operations, different numbers.

The Doctor: There was a goblin, or a trickster, or a warrior... A nameless, terrible thing, soaked in the blood of a billion galaxies. The most feared being in all the cosmos. And nothing could stop it, or hold it, or reason with it. One day it would just drop out of the sky and tear down your world.
Amy: But how did it end up in there?
The Doctor: You know fairy tales. A good wizard tricked it.
River Song: I hate good wizards in fairy tales; they always turn out to be him.

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yes, i need the answer on how to solve

sin x = 3/5

I have tried the usual methods like a unit circle, and stuff but it seems impossible. i need x, an exact number like (square-root)3/2, not a calculator answer like .123431

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Friend says its impossible. I Really dislike my teacher. This sucks.

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Yeah...well, I mean, if it's a triangle designated x, it'll have an opposite side of 3 and a hypotenuse of 5, making the adjacent side 4...maybe you're supposed to draw triangle x?

The Doctor: There was a goblin, or a trickster, or a warrior... A nameless, terrible thing, soaked in the blood of a billion galaxies. The most feared being in all the cosmos. And nothing could stop it, or hold it, or reason with it. One day it would just drop out of the sky and tear down your world.
Amy: But how did it end up in there?
The Doctor: You know fairy tales. A good wizard tricked it.
River Song: I hate good wizards in fairy tales; they always turn out to be him.

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Sine tables. Look up the value of 3/5 (0.6). Its somewhere between 30 and 40 degrees.

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Naw my teacher gave probs to study with. And i was stuck on like 5. He said no calculators on the test. All 5 I were stuck on(1 was the one i posted here) required calculators.

He just didnt check the problems. I spent all my time trying to figure that out and not memorizing the Double angle formulas and identities. Im kinda PO.

Sorry just lock this if you wish. Thanks for trying to help

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When I went to school (Ok, it was a while ago) Log tables (with Sine, Cosine, Tangent and the anti-versions) were considered legal and essential in exams. The problem with calculators was that they could store stuff, and not just present data in table form.

They give precision to four decimal places in an easy lookup table. I suggest you inquire as to their legality.

Specifically we used Eton Statistical & Math Tables. I still have mine (any carry it with me). Its only 29 years old!

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I'll give you a hint.

sin(X) is a math operation that matches X up against a table of numbers. So, think of it as a vairable by the means of Y

Now you have Y X = 3 / 5

Solve for X, then use the multiplication and division of fractions properties to realize that you now have the following:

X = (1 / Y) ( 3 / 5)

Changing a variable from B into 1 / B is called the 'inverse of' B. So, in reality you actually have this:

X = Y ^ -1 (3 / 5)

Replace Y with sin, and you have your answer to this question.

X = sin^-1 (3 / 5)

Win the game.

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sin^-1 is Cosecent

And I asked him the morning before the test and it was impossible with our methods.

And mike ryan, that was cool BUt i still dont see how that could have helped me...

Thanks for the help guys .

We should ask a mod for a homework help Topic. You can post if you need help in

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Pretty good idea actually.

Hatred does not cease by hatred, but only by love; this is the eternal rule.
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Pretty good idea actually.

I second that one!

I think I'll need some help when I'll begin my higher studies, so I think it's a great idea.

As long as it isn't abused, of course... :wink:

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How could it be abused?

You could make the rules be:

1. This is for homework help, we are not going to do your homework for you. Two examples allowed. None more

2. If Nobody responds, dont spam/bump. The problem may be nobody remembers/knows how to do it.

3. Asking for help with concepts is one thing, but asking for someone to do your statistics homework is another. If you have the resources and just dont quite get it. We can help.

4.This thread is for quick responses, try to be fast, yet thorough. Please do not spam.

Something like that ?

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How could it be abused?

You could make the rules be:

1. This is for homework help, we are not going to do your homework for you. Two examples allowed. None more

2. If Nobody responds, dont spam/bump. The problem may be nobody remembers/knows how to do it.

3. Asking for help with concepts is one thing, but asking for someone to do your statistics homework is another. If you have the resources and just dont quite get it. We can help.

4.This thread is for quick responses, try to be fast, yet thorough. Please do not spam.

Something like that ?

Besides, if people can can explain it well over the internet, I'm quite sure teachers will agree as long as it isn't being done for you.

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No real purpose over the summer. But we'll consider it this fall.

Unless our year-long school contingent is bigger than I expected...

The Doctor: There was a goblin, or a trickster, or a warrior... A nameless, terrible thing, soaked in the blood of a billion galaxies. The most feared being in all the cosmos. And nothing could stop it, or hold it, or reason with it. One day it would just drop out of the sky and tear down your world.
Amy: But how did it end up in there?
The Doctor: You know fairy tales. A good wizard tricked it.
River Song: I hate good wizards in fairy tales; they always turn out to be him.

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Cool, looking forward to in enxt year with math analysis and chemistry ap

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How could it be abused?

Belive me, I've seen topics like this being abused...

Some people posted impossible tasks and stuff like that just to annoy others etc..

I think it would work well in this forum though. :wink:

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