check all that apply. If csc theta = 13/12 then: a. tan theta = 12/5 b. sin theta = 12/13 c. cos theta = 12/13 d. sec theta = 12/13
\(\bf csc(\theta)=\cfrac{13}{12}\implies \cfrac{hypotenuse}{opposite}\implies \cfrac{c=13}{b=12}\\ \quad \\ \textit{using the pythagorean theorem }c^2={\color{blue}{ a}}^2+b^2\implies \sqrt{c^2-b^2}={\color{blue}{ a}}\) once you find "a", or adjacent side, check against your choices
keeping in mind -> http://www.mathplanet.com/images/math/codecogs_cbc49307.gif
a = 25
how would i check?
a = 25?
I think so but how would i find out what else works?
\(\bf c^2={\color{blue}{ a}}^2+b^2\implies \sqrt{c^2-b^2}={\color{blue}{ a}}\implies \sqrt{13^2-12^2}={\color{blue}{ a}}\) you plug in your a, b and c, in the trig identities given, tangent, sine, cosine, secant see if they match with the values for "a", "b", and "c" that you have
So would the answer be B, and C?
\(\bf \sqrt{13^2-12^2}={\color{blue}{ a}}\implies \sqrt{169-144}=a\implies \sqrt{25}=a\implies 5=a\\ \quad \\ \textit{let's test the first choice, say }tan(\theta)\\ \quad \\ tan(\theta)=\cfrac{b}{a}\implies \cfrac{13}{5}\) there's no 1 answer all may be correct or some of them only so you'd have to check all
hmmm dohhh I meant 12.. lemme fix that \(\bf \sqrt{13^2-12^2}={\color{blue}{ a}}\implies \sqrt{169-144}=a\implies \sqrt{25}=a\implies 5=a\\ \quad \\ \textit{let's test the first choice, say }tan(\theta)\\ \quad \\ tan(\theta)=\cfrac{b}{a}\implies \cfrac{12}{5}\)
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so as you can see, the 1st checks out
Oh ok, so it would end up being A and B right
yeap
alright, thanks
yw
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