# Trigonometric function of x

The angle of elevation from the top of a house to a jet flying 2 miles above the house is x radians. If d represents the horizontal distance, in miles, of the jet from the house, express d in terms of a trigonometric function of x. The graph the function for 0< x <pi.

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Did you draw a right triangle involving x, d and 2 miles? That's a good place to start.

yes I did, now what?

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From your triangle with d, x, and 2 labeled can you think of a trig function that involves them?

no, thats why I am asking...

ok, this is what I need to figure out. tan x=opp/adj = ?/?

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ok, this is what I need to figure out. tan x=opp/adj = ?/?

Very much so. Skip the last = ?/?. Just substitute the values for opp and adj.

well if I knew what they were I could..lol

maybe this graph will help..

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well if I knew what they were I could..lol

I'm starting to feel helpless here. You drew the picture, right? It should be right in front of you. Which is the adjacent side and which is the opposite side to the angle x?

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maybe this graph will help..

How can you not know with such a gorgeous picture to help? Which leg is opposite the angle x and which is adjacent?

the 2 mile side would be the opposite and the other would be the adjacent side.

I have never done this before, so that is why I am lost...No I didnt draw the picture. It is supposed to help me.

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the 2 mile side would be the opposite and the other would be the adjacent side.

Yes, so tan(x)=... just fill it in.

tan(x)=2/? Grrrrrr

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the 2 mile side would be the opposite and the other would be the adjacent side.

No offense, but this is getting to be like pulling teeth. The 'other' i.e. the 'adjacent side' is clearly labelled in your picture. It has a letter on it.

tax(x)=2/d

I do understand your frustration with me, just think how I feel.. :(

I was wondering why do I need to forget the ?/?....

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I was wondering why do I need to forget the ?/?....

I just meant you should fill in the ??'s. tan(x)=2/d is exactly what you want. You are basically done. Now just solve for d.

I truly don't know how to solve for d. I must sound pretty stupid, huh?

ok wait, is it d=2cot(x) ?

oops, I mean 2/tan(x)

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ok wait, is it d=2cot(x) ?

Sure. That's more than brilliant. I was hoping for just d=2/tan(x). But that's the same if not better.

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oops, I mean 2/tan(x)

2/tan(x)=2*cot(x).