Okay, so I'm doing some trig identities...

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Okay, so I'm doing some trig identities and realize I'm not entirely sure how dividing fractions work.

Like I understand that a/b/c/d would mean a/b * d/c = ad/bc

Then I got to something like

1 / 1-sinx / cosx

What I see is 1 / 1-sinx / cosx / 1, so I ended up doing 1 / 1-sinx * 1 / cosx = 1 / cosx (1-sinx), which is wrong and I'm suppose to get cosx / 1-sinx.

So basically, question is how am I suppose to view a/b/c as?

Does it mean a/b / c/1 or a/1 / b/c?

Also, it would be great if someone can help me understand how a/b/c/d/e would work. I've yet to come to something like this, but I would be completely lost if it ever shows up.

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>>28697

you wouldnt happen to the the guy needing help with trig homework in an earlier thread would you?

Your problem is notation. No one uses division like that, so when you're doing your identities remember your order of operations and use fucking parentheses. a/b/c just makes me rage.

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>>28697

>1 / 1-sinx / cosx

>What I see is 1 / 1-sinx / cosx / 1, so I ended up doing 1 / 1-sinx * 1 / cosx = 1 / cosx (1-sinx), which is wrong and I'm suppose to get cosx / 1-sinx.

write it down on paper then show us it. We're on an image board after all.

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>>28711

No, first time posting on this board. Also, I guess I should say I'm having problems with reading fractions rather than division.

And my question is about how to read a fraction in the form of a/b/c

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>>28718

>a/b/c

you wouldn't normally encounter a fraction like that unless someone notated wrong. You'd be able to tell if it was (a/b)/(c/1) or (a/1)/(b/c) following the problem; Besides they are equivalent, see the associative property.

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>>28718

you dont read fraction in the form of a/b/c because its ambiguous.

a/b/c could be either (a/b)/c which is a/bc or a/(b/c) which = ac/b. Math books and texts will never have this kind of shit. Board posts might because people are retarded.

When you do your own math later it may be acceptable to you to use something like a/b/c because you're keeping track of which operation you are doing when. In a practical sense you will never see something like a/b/c with no indication of which division to perform first. a/b/c/d/e is simply absurd.

You said you had something like 1/1-sin(x)/cos(x) please show me this because no one should ever put such a thing down.

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>>28723

>a/b/c could be either (a/b)/c which is a/bc or a/(b/c) which = ac/b

This is what I'm having problem understand. I don't know when they mean which

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>>28724

on the second row first fraction as an example you can think of it as

(1/1)/((1/cosx) - (sinx/cosx))

(1/1) * ((cosx/1)-(cosx/sinx))

common denominators from here

I'm out, you should see if you can get a solution to the problem for reference. (solution meaning step-by-step, not a straight up answer)

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>>28724

ok, since you are simplifying and modifying the denomiator you MUST use parentheses there. that will help you keep track of things. see attached

In general, when ever you are converting something into a fraction, as you did with tan and sec you MUST put parenthesis around it. section it off in your mind and on the paper. then you know how to manipulate it from there.

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>>28730

No, I don't have problem solving it after realizing that I'm suppose to see the fraction as a/(b/c).

I just want to understand when I'm suppose to view a/(b/c), and when to view (a/b)/c

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>>28727

gonna same fag real quick here

since you wont ever see a/b/c unless someone is trolling you or just not notating, YOU make it happen.

In your problem you put the steps into an a/b/c setup because you didnt notate well. since it was originally an a/b, when you modified sec(x) and tan(x) you need to then notate that. It would then be a/(b/c) = ac/b. Just keep track of things.

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>>28743

fraction can be confusing but only if you make them so. Just be rigorous. In math, if you change something, either by simplifying or cross canceling or converting via identity NOTE that with parenthesis. Then you can always tell where you're at and what youre doing.

In school they always say "show your work. Show all the steps" its not just to reinforce practices in your mind. Its to make things like this, which are born out of laxness on both yours and your instructors part. It may be annoying and grindy to show all those steps, but you'll always be able to find your mistake, or try to sort out your confusion if you have everything infront of you.

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>>28697

One problem that you had is with the proper notation of fractions.

When using horizontal bars, you put the main bar in-line with the operation and the equal signs, and make it longer than any other line in the fraction.

The pic shows how the fractions are usually set (but I prefer even longer main fraction bars).

But beware, if your teacher doesn't use this notation you may get lower scores. If not sure, ask or use parentheses.

When using the solidus (/) like in your text you don't have this hint, so many other posters complained about it. In this case you should always use parentheses.

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Not sure if you still need help, but I was taught to do it as a multiplication sandwich.

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