1 + sinX + cosX (1 + sinX + cosX)²
---------------- = -----------------------------------
1 + sinX - cosX (1 + sinX - cosX)(1 + sinX + cosX)²
1 + 2sinX + 2cosX + 2sinXcosX + (sinX)² + (cosX)
= -----------------------------------------------------
1 + 2sinX + (sinX)² - (cosX)²
Now, notice almost everything has a coefficient of 2. Substituting 1
for (sinX)² + (cosX)² in the numerator and (sinX)² for 1 - (cosX)²
in the denominator gives
2 + 2sinX + 2cosX + 2sinXcosX
= -------------------------------
2sinX + 2(sinX)²
Factor by grouping in the numerator, and factor out sinX in the
denominator
(1 + sinX)(1 + cosX)
= ----------------------
(1 + sinX)sinX
Dividing numerator and denominator by 1+sinX gives
1 + cosX
= -----------
sinX
2007-12-06 21:26:07
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answer #1
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answered by iceman 7
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1. ( secx/sinx) - (sinx/cosx) = ( 1 / sin x cos x) - ( sinx / cos x) = ( 1 - sin^2 x)/ (sin x cos x) = cos^2 x / (sin x cos x) = cos x / sin x = cot x ans. 2. (1/1-cosx) + (1/1+cosx) = (1 + cosx + 1 - cosx ) / ( 1-cosx) ( 1+cosx) = 2 / ( 1 - cos^2 x) = 2 / sin^2 x = 2csc^2x
2016-05-21 23:41:03
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answer #2
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answered by ? 3
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(1 + sinx + cosx) / (1 +sinx -- cosx)
= {sinx + (1 + cosx)} / {sinx + (1 -- cosx)}
= {2sinx/2cosx/2 + 2cos^2x/2} / {2sinx/2cosx/2 + 2sin^2x/2}
= 2cosx/2(sinx/2 + cosx/2) / 2sinx/2(cosx/2 + sinx/2)
= 2cosx/2 / 2sinx/2
= cotx/2
2007-12-06 21:44:46
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answer #3
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answered by sv 7
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(1+ sin x + cos x)/(1+ sin x - cos x)
as RHS is in x/2 we reduce to x/2
sin x = 2 sin x/2 cos x/2
1+ cos x = 2 cos ^2 x/2
so 1+ cos x + sin x = 2 cox x/2(sin x/2+ cos x/2)
1- cos x = 2 sin ^2 x/2
1- cos x + sin x = 2 sin ^2 x/2 + 2 sin x/2 cos x/2
= 2 sin x/2(sin x/2 + cos x/2)
by division we get the result
2007-12-06 21:36:19
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answer #4
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answered by Mein Hoon Na 7
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2sinx/2 cosx/2 + 2cos^2x/2
-------------------------------------
2sinx/2 cosx/2 + 2sin^2x/2
= cotx/2
2007-12-06 21:57:02
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answer #5
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answered by Hari 2
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i would think that it means -tan...but thats just me....i kinda forgot the whole calculus thing
2007-12-06 21:21:09
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answer #6
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answered by Jagman S 2
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not complete
2007-12-06 22:12:42
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answer #7
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answered by CPUcate 6
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