trig problem.. help pls
\[f(\theta) = \frac{ 1 - \cos \theta}{ 4\sin \theta - 3\cos \theta + 6 }\]
?
\[\theta \epsilon \mathbb{R} \]
prove that for the all values of theta \[0 \le f(\theta) \le \frac{ 6 }{ 11 }\]
i don;t even have slightest clue for this problem... :/
@dumbcow , @agent0smith , @phi @Hero , @ganeshie8 , @ehuman pls help
@ranga
so it must be a cyclic, so can't you find the maximum and minimum to give you the limits,
huh ?
I know i have to fimd max and min but how ?
who wants a medal and a fan ? give me one ill give you one ^_^
Find f'(theta) and set it to 0. Solve for theta. Those will be the critical points (meaning potential max/min points).
do you know calculus ?
that's the problem... I don't know calculus yet
i mean i haven;t learned anything under the topic calculus. but I think we have learned the base for calculus...
according to my knowledge... i think that both numerator and denominator should contain the same trig function in order to calculate the max and min... i mean it was the base for the ones i've solved.. but none of them were in the form of a division...
With a graphing calculator I can see that the statement is true, but I don't know how to evaluate this manually.
hmm well the old fashion way is plot points using unit circle, that will give you idea of graph and turning points....then plug in other values near turning points and you should see a trend toward min of 0, max of 6/11
but how can i prove this ? dumbcow
Plot
the proof is that limit of slope of tangent line goes to 0......hence derivative and calculus :{
I have to get to class, later.
the irony is that calculus is what gives us the proof
I can teel you that thr roots are at +2pi(k) k = innterger
I don't know whether this will help u guys to get an idea.. but so far the problems i've solved in this exercise were linear ones.. so all i had to do was turn all sin , cos, tan value in to a one form .. then get the answer.. so i think this one has to be solved in the same way... but this is a division.. so I can't guess wt to do :/
i guess i;m on my own in this problem... anyway thank u guys :/
you can also use a calculator to find the max and min values, doesn't require calculus. Not sure if there's an easy way to simplify that original function, though
http://www.wolframalpha.com/input/?i=f%28%5Ctheta%29+%3D+%5Cfrac%7B+1+-+%5Ccos+%5Ctheta%7D%7B+4%5Csin+%5Ctheta+-+3%5Ccos+%5Ctheta+%2B+6++%7D ^ none of the alternate forms are helpful
So w/o calculus i'd think you'd need to use a graphing calc.
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