Mathematics
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OpenStudy (laddiusmaximus):
(sinx/(1+cosx)) +((1+cosx)/sinx) totally lost
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OpenStudy (anonymous):
What do you have to do? prove it?
OpenStudy (laddiusmaximus):
yeah=2cscx
myininaya (myininaya):
combine the fractions by finding a common denominator
OpenStudy (laddiusmaximus):
yeah i got that, but what do I use, sinx? or 1+cosx?
OpenStudy (anonymous):
I'm working on it
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OpenStudy (anonymous):
The Common Denominator will be sinx(1+cosx)
myininaya (myininaya):
what do you mean? how to combine these fractions: 2/3+5/7
OpenStudy (laddiusmaximus):
so the common denominator is (sinx)1+cosx?
myininaya (myininaya):
sinx(1+cosx)
OpenStudy (anonymous):
yes that is the common denom
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OpenStudy (laddiusmaximus):
okay so now I have (sinx^2x(1+cosx)/sinx(1+cosx)) + (sinx(2+cos^2x)/sinx(1+cosx))?
myininaya (myininaya):
you will have (sinx)^2+(1+cosx)^2 in the numerator and sinx(1+cosx) is the denominator
OpenStudy (laddiusmaximus):
sin^2x on both sides?
OpenStudy (anonymous):
I think you should have this so far: \[\sin^2x + (1+cosx)^2/sinx(1+cosx)\]
myininaya (myininaya):
ok look at your first fraction. what does the bottom lack so that it has the same denominator as the 2nd. sinx, right?
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myininaya (myininaya):
multiply both the top and bottom by sinx on the first fraction
OpenStudy (laddiusmaximus):
hmm i had [\sin^2x(1+cosx)+sinx(2+\cos^2x)/sinx(1+cosx)\]
myininaya (myininaya):
now look at the 2nd fraction what does the bottom lack so that it has the same denominator as the first fraction, (1+cosx), right?
myininaya (myininaya):
so multiply the top and bottom of the 2nd fraction by (1+cosx). Now the fractions have the same denominator, you can write it as one fraction now
OpenStudy (laddiusmaximus):
I follow you so far.
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myininaya (myininaya):
so we have [sinx*sinx+(1+cosx)(1+cosx)]/[sinx(1+cosx)]
myininaya (myininaya):
[(sinx)^2+1+2cosx+(cosx)^2]/[sinx(1+cosx)]
OpenStudy (anonymous):
I think I got the complete answer/proof
myininaya (myininaya):
what is (sinx)^2+(cosx)^2
OpenStudy (anonymous):
=1
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myininaya (myininaya):
lol gj, but i was laddius
OpenStudy (anonymous):
oops sorry
myininaya (myininaya):
but i was asking*
myininaya (myininaya):
do you still follow laddius
OpenStudy (laddiusmaximus):
so the numerator becomes sin^2x + (1+cosx)^2?
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OpenStudy (anonymous):
yes
myininaya (myininaya):
now foil that (1+cosx)^2
OpenStudy (anonymous):
exactly lol
OpenStudy (laddiusmaximus):
so now its 1+2cosx+cosx^2?
OpenStudy (anonymous):
yes!
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myininaya (myininaya):
+(sinx)^2
myininaya (myininaya):
now do you see (sinx)^2+(cosx)^2 anywhere in that numerator
OpenStudy (laddiusmaximus):
ahhhhh pythagorean
myininaya (myininaya):
what do you have now?
OpenStudy (laddiusmaximus):
so now I have 2+2cosx/sinx(1+cosx)
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myininaya (myininaya):
ok what does the numerator terms have in common
OpenStudy (laddiusmaximus):
2?
OpenStudy (anonymous):
HAHA ignore my last 3 posts..
myininaya (myininaya):
does anything cancel?
myininaya (myininaya):
jp?
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OpenStudy (laddiusmaximus):
the 2s cancel, right?
myininaya (myininaya):
no the 1+cosx do
myininaya (myininaya):
so you have 2/sinx
myininaya (myininaya):
which is ....
OpenStudy (laddiusmaximus):
I have 2+2cosx in the numerator
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OpenStudy (laddiusmaximus):
cosx+cosx= 2cosx, right?
myininaya (myininaya):
didnt you say the numerator terms had a 2 in common so factor that out in you have 2(1+cosx)/[sinx(1+cosx)]
OpenStudy (laddiusmaximus):
crap then the (1+cosx) cancel out and im left with 2cscx
myininaya (myininaya):
BINGO!