BROS, PLEASEHELP ME SOLVE THIS TRIG PROBLEM !!!!!!!!!

BROS, PLEASEHELP ME SOLVE THIS TRIG PROBLEM !!!!!!!!!

Other urls found in this thread:

julialang.org/
twitter.com/AnonBabble

HELLLLLLLLLLLLLLLLLP

BUMP

i dont even know what language that is

0.447

TRIGONOMETRY

(B)

I got this hold up OP I will not be cuck

NIGGER

literally before babby tier math.

I KNOPW IM SUPPOSED TO USE THE HALF ANGLE IDENTITY BUT I GET STUCK PUTTING (-3/5) INTO THE COS THETA PART

I DUNNO WTF TO DO HELLLLLLLP

(B) confirmed

Show me what you have so far

(cos(x) + 1)/2 = cos(x)²

If you can't do it with that then you're fucking bad

THE ANSWER SHEET SAYS IT IS D .. NOT B ... I DUNNO HOW TO DO THIS


OKAY ILL DO THAT

that's literally basic math here in Brazil

...

That's not it, OP dealing with trigonometry

samefag

The only reason its - sqrt(5)/5 its because theta is between pi and -3pi/2

that's trigonometry

IT'S SUPPOSED TO BE NEGATIVE SQRT5/5

WRONG!!!!!!!!!!

read this dumbass

You retard, doesn't even know that the solution of x²=a are sqrt(a) AND -sqrt(a).

can't tell if you have alzheimer or autism. probably both.

Try wolfram alpha

how did you take cos(-3/5) and turn it into cos^angle/2 -sin^2angle/2?? ?

Can't be negative
Get Wolfram

Too lazy to write that

you can rewrite cos(theta) as cos(theta/2)² - sin(theta/2)²

The same way as cos(2theta) = cos(theta)² - sin(theta)²

my progress so far............

what about theta/2 >pi/2 implies that sqrt((cos(theta) + 1)/2) = - cos(theta/2) ?

...

...

Nice

can you please show how you do this algebraically ? I'm not supposed to be using a calc and i have no idea who julia is.

You can derive this just by using the pythagorean theorem. How old are you, fucking 12? jfc

should have specified non-calc in the OP, OP. give me a second

btw julialang.org/

btw if this thread goes of the end re-make it in /r/ or smth i'll find u

I solved it alread in /r/!
Greetings from Germany

why specify + and - if the quadrant the angle is in makes the whole thing negative?

use your half angle identity.

Cant you do arccos(-3/5) to find tetha in that range and then do cos(theta/2)?

how do you know x/2 is in quadrant 2 ?

see pic related, you can just approximate it visually

Additional Informations!

Simple.
Omega is between pi and 3/2 pi. IF you divide it by 2, it will allways been greater than pi/2 and smaller than 3/4 pi. This is in quadrant II.

whoops

thank you!!!! im stupid !!!!!

actually yeah cos should be on the other axis in mine
but you get the idea

hahaha i got the bounds wrong to in that pic

i'm such an idiot

pretend the green looks like a reverse D cause it should be pi to 3pi/2 not 0 to 3pi/2

Why is the result of cos(theta) on your y-axis?
cos(x) is allways on the x-axis.
sin(x) is located on the y-axis.

You missmatched sin and cos xD

At least you know to use the half angle identity.... But you dun fucked that all up.

It's cos theta, not cos(-3/5)

Should be square root of [1+(-3/5)]/2

So this is what STEMlords do for fun...

I think I'll stick with saving the world, please.

(or rather, you're welcome)

Which is square root of (2/5)/2

Which is square root of 1/5

Which is D once you rationalize the denom...

stemlord here

so this is what non-stemlords post...

i think i'll stick with not shitting up boards with pictures from reddit

kek

I just want to point out you've mixed -4 and -3 on your little drawing.

>give me attention I'm smart I promise

retard

only if u help me with my homework user

Topology?

measure theory

Ur on ur own

I'm actually just studying for the final exam rn, this was on an assignment lol so it's already done

Lewts.

I might take 1 class this summer. Not sure if they let me though.

Is this a graduate course? They don't offer this at the undergraduate level at my school (though I do go to a shitty state uni).

4th year undergraduate course. My uni is pretty rigorous in some cases; this is in the "pure math" department.

I'm doing pure math at mine but the highest we really go is analysis and modern algebra. I'm not even sure if topology is available to undergraduates here.

lol damn. my uni is considered best or 2nd best in Canada, so I don't know much about the US.
Analysis is pretty standard for undergraduate, and sometimes it includes basic elements of measure theory like Lebesgue measure and integration.

With that said, going to grad school with only analysis would be fine in most cases.

I'm going to Statistics master's so I need the measure theory for probability theory, since I'm focusing on stochastic processes and stochastic DEs

By what factor do you multiply to double the volume of a pie? Radius is 4cm but that's not enough?

It's cubic root but seriously how. I tried pluging numbers

I was curious as to if you were doing something statistics related, since, from what I've heard / read, theoretical probability is practically measure theory applied to the interval [0, 1]. I did a dual major in bio and pure math, with a minor in statistics. Not sure what I'm going to do with it yet kek

Bump

What is the formula for the volume of a pie lol

The answer is B.
cos-1(-3/5) = 126,8699
cos(126.8699/2) = 0,4472
0.4472 = square root of 5 / 5

I'm confused :c

I think it was cake. But how

that's correct; a CDF is actually a Lebesgue-Stieltjes integral with the measure of the entire space being 1.
i.e the probability is actually a measure