Mathematics
10 Online
OpenStudy (anonymous):
Trig identities?
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
Find cot θ if \[\csc \theta=\frac{ \sqrt{17} }{ 4 }\] and tan θ > 0.
OpenStudy (anonymous):
\[1+\cot ^{2}\theta=\csc^{2}\theta\]
OpenStudy (anonymous):
so from the information provided
OpenStudy (anonymous):
so cot^2=sqrt(17)/4-1
OpenStudy (anonymous):
\[\csc \theta=\frac{ \sqrt{17} }{ 4 }\Rightarrow \csc^2 \theta = \frac{ 17 }{ 16 }\]by squaring both sides
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
Okay so that would then be 1/16 if you subtract the 1?
OpenStudy (anonymous):
\[\cot ^{2}\theta= \frac{ 17 }{ 16 }-1\]
OpenStudy (anonymous):
\[\cot ^{2}\theta= \frac{ 1 }{ 16 }\]
OpenStudy (anonymous):
take the sqrt of both sides
OpenStudy (anonymous):
okay so I was right. so next you sqrt and get cot=sqrt(1)/4
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
\[\cot=\frac{ \sqrt{1} }{ 4 }\]
OpenStudy (anonymous):
take the inverse of the function now and sqrt of 1 is 1
OpenStudy (anonymous):
thata = arctan(1/4), now i don't know at your level do you use +-sign or not
OpenStudy (anonymous):
yes I do
OpenStudy (anonymous):
and do you have to find all solutions, or is the question just on how to use the identity
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
just that 1/4 was the correct answer
OpenStudy (anonymous):
ok good all the best
OpenStudy (anonymous):
thank you for you help
OpenStudy (anonymous):
but know that later at advanced levels there will be more than one solution for this equation
OpenStudy (anonymous):
anytime if you have any question let me know
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
Just to know, what equation would I use to for Find tan θ if sec θ = sqrt(37)/6 and sin θ < 0.
OpenStudy (anonymous):
1+tan^2=sec^2?
OpenStudy (anonymous):
the same equation you just used but instead of cot you use tan and instead of csc you use sec
OpenStudy (anonymous):
i wrote it this way so you will never forget the identity
OpenStudy (anonymous):
okay thanks
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
you are clever girl you learn quick
OpenStudy (anonymous):
i will put the identity for you
OpenStudy (anonymous):
\[1+\tan ^{2}\theta=\sec^{2}\theta\]
OpenStudy (anonymous):
thanks for all your help!
OpenStudy (anonymous):
recall the last identity\[1+\cot ^{2}\theta=\csc^{2}\theta\]
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
all the best good luck