check all that apply. if cot theta= 3/4 and the terminal point determined by theta is in quadrant 3, then: (a) tan theta= 4/3 (b) csc theta = -5/3 (c) sin theta= 3/5 (d) cos theta = -3/5
@jdoe0001 can you please help
\(\bf cot(\theta)=\cfrac{3}{4}\implies \cfrac{adjacent}{opposite}\implies \cfrac{a}{b}\\ \quad \\ \textit{using the pythagorean theorem }{\color{blue}{ c}}^2=a^2+b^2\implies {\color{blue}{ c}}=\pm \sqrt{a^2+b^2}\) the pythagorean theorem doesn't tell us if the root will be negative or positive, but we know that the angle is in Quadrant III, that is, cosine, or "x", is negative and sine, or "y", is negative as well thus we can say that \(\bf cot(\theta)=\cfrac{3}{4}\implies \cfrac{adjacent}{opposite}\implies \cfrac{a=-3}{b=-4}\)
once you have all sides, that is, "a", "b", and "c", then check which ones are correct from the given options, that is, which ones apply
I should point out that also the pythagorean theorem doesn't tell us if the root will be negative or positive, for "c" doesn't really matter, since the radius is always positive
Thanks!
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so would the answer be B and D?
@cwrw238
@jdoe0001
hmmm what did you for "c" anyway?
???
\(\bf cot(\theta)=\cfrac{3}{4}\implies \cfrac{adjacent}{opposite}\implies \cfrac{a}{b}\\ \quad \\ \textit{using the pythagorean theorem }{\color{blue}{ c}}^2=a^2+b^2\implies {\color{blue}{ c}}=\pm \sqrt{a^2+b^2}\)
keep in mind both "a" and "b" are negative
C = 5?
-5
yeap, so well, is "5" since "c" is just the radius, thus is never negative so would the answer be B and D? \(\Large \checkmark\)
so i was right
well, le'ts notice A option as well \(\bf tan(\theta)=\cfrac{b}{a}\implies \cfrac{-4}{-3}\implies \cfrac{4}{3}\)
so, that one applies too
oh ok, i should've seen that one. it's the simplest one lol :p thanks btw
yw
hmmm come to think B doesn't apply
what do you mean?
\(\bf csc(\theta)=\cfrac{c}{b}\implies \cfrac{5}{-4}\implies -\cfrac{5}{4}\)
oh you're right
@jdoe0001 can you help me with one more please
ok.... would be easier if you repost anew, thus more exposure anyway, and we can also revise each other
the answer is a and d right?
yes
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