Evaluate to four decimal places
Please explain how you found your answer
cot183

Question

Evaluate to four decimal places
Please explain how you found your answer
cot183

campbell_st · Answer

find tan(183) which is 3rd quadrant, positive and has the same value as

tan(3)    (3rd quadrant angles are 180 + x) 

when you know 

tan (3) take the reciprocal to find cot (183) which is the same as cot(3)

hope this makes sense.

anonymous · Answer

what reciprocal?

anonymous · Answer

and what is tan 3? and what does this all mean??? i'm so confused

campbell_st · Answer

turn it up side down 

so if you have 2/3 the reciprocal is 3/2 

you calculator may have a key

$$x^{-1} $$

when you get the answer for tan(3) press the button of find

$$\frac{1}{\tan(3)}$$

anonymous · Answer

but why tan3? Where do you get that?

campbell_st · Answer

its a 3rd quadrant angle 

and tan is positive, so cot is positive. 

the angle is the same as 

(180 + x)  in this question x = 3  

so you are really finding cot(3) = 1/tan(3)

anonymous · Answer

is there another method of doing that? like how do you put it in your calculator?

campbell_st · Answer

ok... so have you learnt about angles in any quadrant

|dw:1359953927509:dw|

campbell_st · Answer

yep the easy way to do it is to graph cot(x) then look at the value where x = 183

anonymous · Answer

...how do you graph that on a ti-84 ?? please help

campbell_st · Answer

ok... so do you have a y = key under the screen on the left...?

anonymous · Answer

yes

campbell_st · Answer

ok... press it

anonymous · Answer

alright

campbell_st · Answer

so the cursor is next to the 1st equals sign..?

type   1/tan(x)           press the tan key and in the brackets just press x

I think you have an (x, r Theta) button.

anonymous · Answer

got it

campbell_st · Answer

once you have entered it press enter... 

you maky have to press the window key to change the graph..

campbell_st · Answer

set the x values to min180, max 270 scale 50

campbell_st · Answer

when you have the graph... press the trace key, at the top under the screen and enter 183... it will show a value.

campbell_st · Answer

good luck

anonymous · Answer

sweet I got it! THank you very much :)!

anonymous · Answer

do you always set your x values to min180, max 270 scale 50?

campbell_st · Answer

the angle you were looking at was 183 which is between 180 and 270

set the x value to either side of your desired value... graphing in units of 90 degrees give you the opportunity to see a graph...

campbell_st · Answer

you can adjust the scale to something smaller... if you wish