if cos+cos2? =1 then prove that sin12?+3sin10?+3sin8?+sin6?+ 2sin4?+2sin2?-2=1 2. sec?=x+{1/4x}prove that sec?+tan?=2x or(1/2x) 3. cosec?-sin?=L and sec?-cos? =m,then prove that L2m2(L2+m2+3)=1 4. prove that the external bisector of an angle of a triangle divides the opposite side externally in the ratio of the sides containing the angle. 5. o is ay point inside a triangle ABC.The bisector OD,OE and OF of angle AOB,BOC,COA meets the sides AB,BC and CA in the point D,E,F respectively.Show that AD*BE*CF=DB*EC*FA. please give the answers as soon as possible as the day after tomorrow is my maths exam and there is no mistake in a quetions

Asked by  | 6th Sep, 2012, 07:04: PM

Expert Answer:

Some of your questions are not clear due to some missing symbols and unclear super and sub scripts. Please ask one questions in one post.


 

Answered by  | 6th Sep, 2012, 11:10: PM

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