plzzz give me the answer of these problems step by step
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Hope this helps u a lot
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Avik2001:
no man
i want step by step
not in digits
kon
mai jhaat
hu
kaat
dunga
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Cos 15 =cos (45-30)
Use formula cos(x-y)=cosx cosy+ Sinx siny
=cos45.cos30+ sin45.sin30
Put the corresponding values
cos(15)=(-/3+1)\2-/2
Cos (-75)= cos (75)=cos(45+30)
In general
Cos(x+y)= cosx cosy- sinx Siny
Cos (75)= cos45.cos30 - sin 45.sin 30
=(-/3-1)/2-/2
-/ is root
Sec75= 1/cos75
=(2-/2)/(-/3-1)
Use formula cos(x-y)=cosx cosy+ Sinx siny
=cos45.cos30+ sin45.sin30
Put the corresponding values
cos(15)=(-/3+1)\2-/2
Cos (-75)= cos (75)=cos(45+30)
In general
Cos(x+y)= cosx cosy- sinx Siny
Cos (75)= cos45.cos30 - sin 45.sin 30
=(-/3-1)/2-/2
-/ is root
Sec75= 1/cos75
=(2-/2)/(-/3-1)
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