Question
Thu September 06, 2012 By:

# 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

Thu September 06, 2012

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.

Related Questions
Sun November 19, 2017

# Ohh.... Tq Q1. Prove that( cosecA - sinA) (secA - cosA) = 1/ tanA - cotA.

Sat November 18, 2017

Home Work Help