Math helps please!

[gt_killa]

Here's the problem

write arccos(x/2) in algebraic form (hint: use a triangle)


Thank you!

[Shuemue]

i*({<|}0.467)/4

[Kainsin]

Well, it's been a while since I've taken a math course, so I'm not really sure what "algebraic form" means off the top of my head.

If you're looking at a right triangle with one angle being theta, then cos(theta) = adjacent/hypotenuse. That means arccos(adjacent/hypotenuse) = theta. So the side adjacent to theta is x, the hypotenuse is 2 and the opposite side is sqrt(4 - x^2).

I'm not sure if that helps since I don't really know what the question wants as an answer.

[divisortheory]

Here's the problem

write arccos(x/2) in algebraic form (hint: use a triangle)


Thank you!

Is it possible you misstated the question, and it's actually something like sin(arccos(x/2))?

[Correction]

Oh god school's back in session. Here come the 'I can't do my homework do it for me /bg/' threads again.

[souleman]

-1/sqrt(4-x^2)

[divisortheory]

-1/sqrt(4-x^2)

That's definitely an answer to a question, but it isn't the question that the OP asked.

[Charla]

Oh god school's back in session. Here come the 'I can't do my homework do it for me /bg/' threads again.

Look on the bright side, it's more opportunities to throw in variations of divided by zero!

[Osede]

-1/sqrt(4-x^2)

That's definitely an answer to a question, but it isn't the question that the OP asked.

isn't this is the derivative of arccos, d/dx (arccos(x/2)) ?

OP then just try to intergrate this function then , have fun >.>

[divisortheory]

-1/sqrt(4-x^2)

That's definitely an answer to a question, but it isn't the question that the OP asked.

isn't this is the derivative of arccos, d/dx (arccos(x/2)) ?

OP then just try to intergrate this function then , have fun >.>

Close, it's half of the derivative. it's also -csc(arccos(x/2))/2.

But since the OP's question doesn't make any sense really, it's hard to know what he was asking.

[Osede]

meh. i'm feel bad i'm master grad but can't solve the problem lol

[divisortheory]

meh. i'm feel bad i'm master grad but can't solve the problem lol

Don't feel bad, problem doesn't make any sense lol.

[Octavious]

I think your close to what it should be though, i finished my calc last quarter, so it's fuzzy but if memory serves I remember a section of something involving the sin(arccos(x/2))? or something, I remember the example using a triangle too...if I wasnt at work i'd so whip out my old notebook...lol

[divisortheory]

Even if that's it though, is it sin(arccos(x/2)), tan(arccos(x/2)), sec(arccos(x/2)), csc(arccos(x/2)), or cot(arccos(x/2))?

[souleman]

Sorry, I couldn't figure out how to write geometric shape in an algebraic form.

[Viena]

Maybe they were thinking in asking this instead?

cos (x/2) = sqrt((1+cos(x))/2)

or the more obvious

arccos (x/2) = pi/2 - arcsin (x/2)

or make some work with Euler formulas, but I assume you are not being teached those anytime soon and doubt that those lead to anything special with x/2.

[gt_killa]

I copied the question exactly from the book word for word D:...Didn't understand what they want to as an answer so I'm just asking for help here. Thank you for trying for so far !

[Charla]

Can't arccos be expressed as something involving e^x, with no explicitly trigonometric terms?

This might help: what class is it for?

[divisortheory]

Can't arccos be expressed as something involving e^x, with no explicitly trigonometric terms?

This might help: what class is it for?

Yea, what class was it for? The hint made me think it was a sin(arccos) problem or something similar, which would mean probably Trig I or something like that

[gt_killa]

It's Calculus 1 ;