Show that cos12+cos60+cos84=cos24+cos48 , Mathematics


=cos 12+cos 60+cos 84

=cos 12+(cos 84+cos 60)

=cos 12+2.cos 72 . cos 12

=(1+2sin 18)cos 12

=(1+2.(√5 -1)/4)cos 12

=(1+.(√5 -1)/2)cos 12

=(√5 +1)/2.cos 12


=cos 48+cos 24

=2cos 36. cos 12

=2.(√5 + 1)/4)cos 12

=(√5 +1)/2.cos 12

 L.H.S = R.H.S

Posted Date: 3/9/2013 8:03:08 AM | Location : United States

Related Discussions:- Show that cos12+cos60+cos84=cos24+cos48 , Assignment Help, Ask Question on Show that cos12+cos60+cos84=cos24+cos48 , Get Answer, Expert's Help, Show that cos12+cos60+cos84=cos24+cos48 Discussions

Write discussion on Show that cos12+cos60+cos84=cos24+cos48
Your posts are moderated
Related Questions
Explain Comparing Mixed Numbers in maths? A mixed number is made up of two parts: a whole number and a fraction. For example: 2(3/4) 2(3/4) is read "two and three-fourths

Solve following  x - x  e 5 x + 2   = 0 . Solution : The primary step is to factor an x out of both terms. DO NOT DIVIDE AN x FROM BOTH TERMS!!!! Note as well that it i

Let 0 ! V1 !    ! Vk ! 0 be a long exact sequence of vector spaces with linear maps. Show that P (??1)i dim Vi = 0.

An observation was made concerning reading abilities of males and females. The observation leads to a conclusion that females are faster readers than males. The observation was bas

Illustration In a social survey whether the main reason was to establish the intelligence quotient or IQ of resident in a provided area, the given results were acquired as tab

Assume that Y 1 (t) and Y 2 (t) are two solutions to (1) and y 1 (t) and y 2 (t) are a fundamental set of solutions to the associated homogeneous differential equation (2) so, Y

What is Monomials and Polynomials in maths? An expression like 7x is called a monomial. A monomial is an integer, a variable, or a product of integers and variables. Other e

Survey 83% of community for a park. Randomly select 21 people if they do or do not want a park. Can you use normal distribution to approximate binomial distribution?If so find mean

Find the normalized differential equation which has {x, xex} as its fundamental set

Laura is planning her wedding. She expects 230 people to attend the wedding, but she has been told that around 5% typically don't show. About how many people should she expect not