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marasofia1616
f(x) = - 2 cot 3x please someone help me find the domain and range of this functions
Do you know the domain and rain for cot?
that its undefined because its domain in standard form is all real #s except pi? I am not sure, I am guessing
Right, the domain of cot(x) is all reals except for integer multiples of pi. So not at 0, pi, 2pi, ...
So if this is cot(3x), then 3x cannot equal n*pi. Now solve for x
do I solve for x by setting 3x = 0?
No. What @Tonks means is "solve of x in terms of n and pi", I believe. He's stating an easy statement in a very formal manner.
No, I mean in a statement like 3x = n*pi, isolate x on one side and everything else on the other by dividing by 3...
Yep. Exactly what I said. ;)
Ok, but how do I get the domain or range from that?
Take the domain of the basic function and think of it geometrically.
|dw:1350961916817:dw| Here is -cotx
Now if you are familiar with transformations, then you know a multiple of x compresses the graph along the x-axis
That compression will move the asymptotes, like an accordion, toward the origin.