Mathematics
7 Online
OpenStudy (anonymous):
Use the fundamental identities to simplify this expression :csc x/cotxsecx PLEASE SHOW ME STEP BY STEP HOW TO GET THE ANSWER!
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (solomonzelman):
here are the rules:
1) \(\large\color{black}{ \csc(x)=\frac{\LARGE 1}{\LARGE \sin(x)} }\)
2) \(\large\color{black}{ \sec(x)=\frac{\LARGE 1}{\LARGE \cos(x)} }\)
3) \(\large\color{black}{ \cot(x)=\frac{\LARGE \cos(x)}{\LARGE \sin(x)} }\)
OpenStudy (solomonzelman):
And the problem is, \(\large\color{black}{ \frac{ \LARGE \csc(x)}{\LARGE \cot(x)\sec(x)} }\) correct?
OpenStudy (anonymous):
yea
OpenStudy (anonymous):
ok i got to that step
OpenStudy (anonymous):
Do you just cancel them out now?
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (solomonzelman):
Which step did you get? I haven't posted any "steps" I posted the rules and the problem.
OpenStudy (anonymous):
The seperation using quotient identity and reciprocal
OpenStudy (solomonzelman):
This is what I would do,
\(\large\color{black}{ \frac{ \LARGE \csc(x)}{\LARGE \cot(x)\sec(x)} }\)
applying rule 3, we get,
\(\large\color{black}{ \frac{ \LARGE \csc(x)}{\frac{\huge\cos(x)}{\huge \sin(x)}\LARGE \sec(x)} }\)
applying rule 2 we get,
\(\large\color{black}{ \frac{ \LARGE \csc(x)}{\frac{\huge\cos(x)}{\huge \sin(x)}~\times~\frac{\huge1}{\huge \cos(x)}} }\)
OpenStudy (solomonzelman):
what cancels?
OpenStudy (anonymous):
the cosines
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (solomonzelman):
yes.
OpenStudy (solomonzelman):
\(\large\color{black}{ \frac{ \LARGE \csc(x)}{\frac{\huge1}{\huge \sin(x)}} }\)
OpenStudy (solomonzelman):
and this is equal to?
OpenStudy (solomonzelman):
(Rule 1)
OpenStudy (anonymous):
1
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (solomonzelman):
Yup !
OpenStudy (anonymous):
1/sin*1/sin
OpenStudy (anonymous):
thank you
OpenStudy (solomonzelman):
the answer is 1
OpenStudy (anonymous):
Could you help me with one more
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (solomonzelman):
yw
OpenStudy (solomonzelman):
I can try, lol;)
OpenStudy (anonymous):
\[\csc^2\theta-\cot^2\theta/\sec\]
OpenStudy (solomonzelman):
just use the same rules, to re-write everything in terms of sine and cosine
OpenStudy (solomonzelman):
Wait, the numerator is csc^2x-cot^2x ?
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (anonymous):
yea
OpenStudy (solomonzelman):
csc^2x = cot^2x+1
for all x values.
OpenStudy (solomonzelman):
So, re-write the numerator, what do you get?
OpenStudy (anonymous):
cot^2x+1-cot^2x
OpenStudy (solomonzelman):
yes
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (solomonzelman):
and that is equal to?
OpenStudy (anonymous):
1/secx
OpenStudy (anonymous):
i mean 1 and then put it over the denominator
OpenStudy (solomonzelman):
yes, and 1/sec(x) is?
OpenStudy (anonymous):
cos x thank you soooo much!
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (solomonzelman):
yes, and 1/sec(x) is?
OpenStudy (solomonzelman):
yes yes, sorry, cos(x)....
OpenStudy (solomonzelman):
Didn't see your freply b4...
OpenStudy (anonymous):
ur fine lol