Prove the Trigonometric Equation sinx/1-cosx +sinx/1+cosx =2cscx
I currently have sinx + sinx/1+cosx
\[\Large \frac{ \sin \theta }{ 1-\cos \theta }+\frac{\sin \theta}{1+\cos \theta}=2\csc \theta\] correct?
Yes
Alright, does it matter if you make the RHS look like the LHS or do you have to simplify the LHS to the RHS
I have to simplify the RHS to the LHS because it's more complex
I mean LHS to the RHS
Alright, well a tip is to work on both sides, get one side simplified to a point and then have the other side "catch up" to it. Anyways this looks simple enough, we just have to go and add the fractions so by getting like denominators we get \[\Large \frac{\sin \theta(1+\cos \theta)+\sin \theta(1-\cos \theta)}{(1-\cos \theta)(1+\cos \theta)}\]
I'm lost
Alright, well you know to add \[\Large \frac{a}{b}+\frac{c}{d}\] that you have to get both fractions with like denominators correct?
Yes
Then you can add the numerators
Never mind I got you
OK, well committ this to memory cause it makes these^^^ a lot faster \[\Large \frac{a}{b}+\frac{c}{d}=\frac{a \cdot d}{b \cdot d}+\frac{c \cdot b}{d \cdot b}=\frac{ad+cb}{db}\]
Okay sorry, it's just looking at that makes me confused carry on
Yeah just take the numerator of the first and multiply it by the denomin of the second then do that for the other fraction and then multiply the denominators, it saves time in simplifying them and then adding them. Anyways we get \[ \Large \frac{\sin \theta+\sin \theta \cos \theta+\sin \theta-\sin \theta\cos \theta}{1-\cos^2 \theta}\]
\[\Large \frac{2\sin \theta}{\sin^2 \theta}\]
Yeah, from there I got 2sin^2x/1-cos^2x
2sin theta/sin ^2 theta
I think you can simplify from there
2*1/sin theta
I'm sorry I don't know what to do next
1/sin theta=csc theta
The sin in the numerator cancels out with one of the sin in the denom.
1-cos^2 theta=sin^2 theta use this identity in the denominator
\[\Large \frac{2\sin \theta}{\sin^2 \theta}= \frac{2\sin \theta}{\sin \theta \cdot \sin \theta}=\frac{2}{\sin \theta}=2 \cdot \frac{1}{\sin \theta}= 2\csc \theta\]
Thanks a bunch dude
Yw
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