Write the following as an algebriac expression in "x"

cot(arccos(3x)), 0 ≤ x ≤ 1/3

Question

Write the following as an algebriac expression in "x"

cot(arccos(3x)),  0 ≤ x ≤ 1/3

misty1212 · Answer

HI!!

anonymous · Answer

This problem makes my head hurt :( lol

misty1212 · Answer

this is really not that bad at all 
first step: draw a triangle with  some angle $\theta$  labelled
next step, since $$\cos(\theta)=3x$$ put a $3x$ on the "adjacent" side and make the hypotenuse 1

misty1212 · Answer

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misty1212 · Answer

there is a picture of an angle whose cosine is $3x$
what you need is the "opposite" side which you find via pythagoras

misty1212 · Answer

let me know what you get
it should have a square root in it

anonymous · Answer

:o let me try

anonymous · Answer

sqrt(-9x^2 + 1) ?

misty1212 · Answer

yes although 
$$\sqrt{1-9x^2}$$ looks neater

anonymous · Answer

haha alright

misty1212 · Answer

now you want the cotangent of that angle, which is 
"adjacent over opposite" so you are pretty much done, just write it i

anonymous · Answer

Yeah I got it form here, you just made that so easy it's ridiculous. Thank you so much

misty1212 · Answer

it is ridiculously easy if you know what you are doing
hope your head does not hurt anymore 
$$\color\magenta\heartsuit$$

anonymous · Answer

It's alleviated :)