can some check cscθ secθ/csc^2θ+sec^2θ csc^2x=1/sin^2x x=1/cosx sec^2x=x1/cosx (1/sin^2x)+(1/cos^2x) how do i simplfy?
@Nnesha
plz someone
is it one question or 4 ? :o
1
i showed my work
i wanted to know if it is correct
alright let me check it is this ur question \[\large\rm \frac{ \csc \theta \sec \theta }{ \csc^2 \theta } =\sec^2 \theta \]
|dw:1446226071480:dw|
ohh okay wait a sec i'll check
k
i don't get what you mean by this `x=1/cosx ` but looks like you're working on the denominator \[\large\rm \frac{ \csc \theta \sec \theta }{ \csc^2 \theta + \sec^2 \theta } \rightarrow \frac{ \csc \theta \sec \theta }{ \frac{ 1 }{ \sin^2\theta }+\frac{ 1 }{ \cos^2 \theta }}\]
yes the denominator
alright good so far now first lets deal with the denominator \[\large\rm \frac{ \csc \theta \sec \theta }{ \csc^2 \theta + \sec^2 \theta } \rightarrow \frac{ \csc \theta \sec \theta }{ \color{Red}{\frac{ 1 }{ \sin^2\theta }+\frac{ 1 }{ \cos^2 \theta } }}\] find common denominator
cos
\[\large\rm \frac{ 1 }{ \sin^2\theta }+\frac{ 1 }{ \cos^2 \theta }\] hmm no both denominators are different so we should multiply them
csc2+sec2
here is an example when we find common denominators \[\large\rm \frac{ 1 }{ x }+\frac{1}{y}\] both denominators aren't the same so we should multiply them \[\frac{ y +x}{ xy }\] and when we find common denominator we should multiply numerator of first fraction by the denominator of 2nd fraction multiply numerator of 2nd fraction by the denominator of first fraction
no we changed csc^2+sec^2 to 1/sin^2theta +1/cos^2
\[\large\rm \frac{ 1 }{ \sin^2\theta }+\frac{ 1 }{ \cos^2 \theta }\] what's common denomiantor ?
2
hmm there isn't any 2 let's say sin^2 theta = a and cos^2 theta = b \[\large\rm \frac{ 1 }{a }+\frac{ 1 }{b}\] what's the common denominator ?
cos
not just cos hmm look at the example i gave you
srry sin would be considered
yes both denominators aren't the same so we should multiply them and btw it's sin^2 and cos^2 not just sin cos
\[\frac{ ??? +??? }{ \sin^2 \theta \cos^2\theta }\] what would you get at the numerator ?
it would be csctheta sectheta
hmm no that's the numerator but i was talking about the numerator of bottom fraction \[\large\rm \frac{ \csc \theta \sec \theta }{ \color{Red}{\frac{ 1 }{ \sin^2\theta }+\frac{ 1 }{ \cos^2 \theta } }}\rightarrow \frac{ csc \theta sec \theta }{\frac{???+??}{sin^2 \theta +cos^2 \theta }}\]
1/sinx 1/cos
here is an example when we find common denominators \[\large\rm \frac{ 1 }{ x }+\frac{1}{y}\] both denominators aren't the same so we should multiply them \[\frac{ y +x}{ xy }\] and when we find common denominator we should multiply numerator of first fraction by the denominator of 2nd fraction multiply numerator of 2nd fraction by the denominator of first fraction
` multiply numerator of first fraction by the denominator of 2nd fraction` `multiply numerator of 2nd fraction by the denominator of first fraction `
so it would be cos theta and sin theta
hmm not just cos it's cos^2
ok
don't forget the sign hmm no that's the numerator \[\huge\rm \ \rm \frac{ csc \theta sec \theta }{\frac{cos^2 \theta +sin^2 theta }{sin^2 \theta *cos^2 \theta }}\] i made a typo earlier it's sin^2 times cos^2 not +
now we can rewrite csc and sec in terms of cos sin \[\huge\rm \frac{ \frac{ 1 }{ \sin \theta } *\frac{1}{\cos^2\theta }}{ \frac{ \cos^2 \theta +\sin^2 \theta }{\sin^2 \theta *\cos^2 \theta}}\]
tr to simplify that remember the special identity \[\sin^2 \theta +\cos^2 \theta =1\]tr to simplify this remember the special identity \[\sin^2 \theta +\cos^2 \theta =1\]
try*
one sec
sure take u time :=)
ur**
sintheta
wait there is a typo
nnesha could you please help me on the question I tagged you in if you can?
\(\color{blue}{\text{Originally Posted by}}\) @Nnesha now we can rewrite csc and sec in terms of cos sin \[\huge\rm \frac{ \frac{ 1 }{ \sin \theta } *\frac{1}{\cos^2\theta }}{ \frac{ \cos^2 \theta +\sin^2 \theta }{\sin^2 \theta *\cos^2 \theta}}\] \(\color{blue}{\text{End of Quote}}\) it's\[\huge\rm \frac{ \frac{ 1 }{ \sin \theta } *\frac{1}{\color{Red}{\cos\theta} }}{ \frac{ \cos^2 \theta +\sin^2 \theta }{\sin^2 \theta *\cos^2 \theta}}\] cos theta
no it 's not sin please show the steps how did you get that
so cos theta is the answer
how did you get tthat ?
ok so sin theta was right
how did you get that please show ur work
i guessed it
after doing all this work now we should guess the answer ???
srry
i also have notes
\[\huge\rm \frac{ \frac{ 1 }{ \sin \theta } *\frac{1}{\cos\theta }}{ \frac{\color{Red}{ \cos^2 \theta +\sin^2 \theta} }{\sin^2 \theta *\cos^2 \theta}}\] cos^2 x+sin^2 x= ??
1
right \[\huge\rm \frac{ \frac{ 1 }{ \sin \theta } *\frac{1}{\cos\theta }}{ \frac{\color{Red}{ 1} }{\sin^2 \theta *\cos^2 \theta}}\] now change division to multiplication
\[\frac{ 1 }{ \sin \theta }*\frac{1}{\cos \theta} = \frac{1}{ \sin \theta*\cos \theta}\]
thats my answer
no.
\[\huge\rm \frac{ \frac{ 1 }{ \sin \theta*cos \theta } }{ \frac{\color{Red}{ 1} }{\sin^2 \theta *\cos^2 \theta}}\] now change division to multiplication
csc3(θ)sec3(θ)
hmm here is an example \[\large\rm \frac{ \frac{ a }{ b } }{ \frac{ c }{ d } }=\frac{ a }{ b }*\frac{ d }{ c }\] multiply top fraction by the `reciprocal ` of the bottom fraction
sine
show me how did you get that ?
i did 1/sintheta*costheta
tag my name ilost ur post
nvm found it
@Nnesha
alright what's the reciprocal of bottom fraction ??
Would it be cos sin
I suck at math
\[\huge\rm \frac{ \color{Red}{\frac{ 1 }{ \sin \theta*cos \theta } }}{ \color{blue}{\frac{ 1 }{\sin^2 \theta *\cos^2 \theta}}}\] what's the reciprocal of bottom fraction ?
this is like pre-calculus but we are dealing with algebra stuff practice will make it easy
here is an example reciprocal of x/y is y/x
Cos theta/sin theta
hmm no \[\frac{ 1 }{ \sin^2 \theta* \cos^2 \theta }\] just flip the fraction !
Sin2theta cos2theta/1
\[\frac{ 1 }{ \cos \theta*\sin \theta } *\frac{\sin^2 \theta \cos^2 \theta}{1}\] now simplify please
Cos theta sin theta
correct
So that's my answer
yep.
Thank you for the help I really do appreciate it:)
np
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