:: FDIFF_6 semantic presentation
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Lm6:
for x being Real holds 1 - (cos (2 * x)) = 2 * ((sin x) ^2 )
Lm7:
for x being Real holds 1 + (cos (2 * x)) = 2 * ((cos x) ^2 )
Lm1:
for x being Real st sin . x > 0 holds
sin . x = ((1 - (cos . x)) * (1 + (cos . x))) #R (1 / 2)
Lm2:
for x being Real st sin . x > 0 & cos . x < 1 & cos . x > - 1 holds
(sin . x) / ((1 - (cos . x)) #R (1 / 2)) = (1 + (cos . x)) #R (1 / 2)
theorem th9: :: FDIFF_6:1
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theorem th15: :: FDIFF_6:2
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Lm3:
for x being Real st sin . x > 0 & cos . x < 1 & cos . x > - 1 holds
(sin . x) / ((1 + (cos . x)) #R (1 / 2)) = (1 - (cos . x)) #R (1 / 2)
theorem th1: :: FDIFF_6:3
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theorem th2: :: FDIFF_6:4
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theorem th3: :: FDIFF_6:5
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theorem :: FDIFF_6:6
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theorem th5: :: FDIFF_6:7
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theorem :: FDIFF_6:8
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theorem :: FDIFF_6:9
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theorem :: FDIFF_6:10
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theorem th10: :: FDIFF_6:11
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theorem :: FDIFF_6:12
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theorem :: FDIFF_6:13
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theorem th13: :: FDIFF_6:14
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theorem :: FDIFF_6:15
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theorem th16: :: FDIFF_6:16
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theorem :: FDIFF_6:17
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theorem :: FDIFF_6:18
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theorem :: FDIFF_6:19
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theorem :: FDIFF_6:20
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theorem :: FDIFF_6:21
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theorem :: FDIFF_6:22
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theorem th23: :: FDIFF_6:23
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theorem :: FDIFF_6:24
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theorem th25: :: FDIFF_6:25
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theorem :: FDIFF_6:26
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theorem th27: :: FDIFF_6:27
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theorem :: FDIFF_6:28
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theorem th29: :: FDIFF_6:29
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theorem :: FDIFF_6:30
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theorem th31: :: FDIFF_6:31
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theorem :: FDIFF_6:32
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theorem :: FDIFF_6:33
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theorem :: FDIFF_6:34
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theorem :: FDIFF_6:35
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theorem :: FDIFF_6:36
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theorem :: FDIFF_6:37
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theorem :: FDIFF_6:38
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theorem :: FDIFF_6:39
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theorem :: FDIFF_6:40
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Lm4:
for Z being open Subset of REAL
for f1 being PartFunc of REAL , REAL st Z c= dom (f1 + (2 (#) sin )) & ( for x being Real st x in Z holds
f1 . x = 1 ) holds
( f1 + (2 (#) sin ) is_differentiable_on Z & ( for x being Real st x in Z holds
((f1 + (2 (#) sin )) `| Z) . x = 2 * (cos . x) ) )
theorem :: FDIFF_6:41
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Lm5:
for Z being open Subset of REAL
for f1 being PartFunc of REAL , REAL st Z c= dom (f1 + (2 (#) cos )) & ( for x being Real st x in Z holds
f1 . x = 1 ) holds
( f1 + (2 (#) cos ) is_differentiable_on Z & ( for x being Real st x in Z holds
((f1 + (2 (#) cos )) `| Z) . x = - (2 * (sin . x)) ) )
theorem :: FDIFF_6:42
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theorem th43: :: FDIFF_6:43
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theorem :: FDIFF_6:44
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theorem :: FDIFF_6:45
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theorem th46: :: FDIFF_6:46
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theorem :: FDIFF_6:47
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theorem :: FDIFF_6:48
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theorem :: FDIFF_6:49
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theorem :: FDIFF_6:50
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