lisaboden54021 lisaboden54021
  • 26-04-2018
  • Mathematics
contestada

Find the exact value of the trigonometric expression given cos (22.5 ).

Respuesta :

Аноним Аноним
  • 29-04-2018
use the identity   cos^2 (a/2) =  1/2 (1 + cos a) so

cos^ 2 22.5  = cos^2 (45/2)  = 1/2 ( 1 + cos 45)  =  1/2(1 + sqrt2/ 2)4 = 1/2 + sqrt2/4

cos 22.5  =  sqrt ( 1/2 + sqrt2/4)  Answer
Answer Link

Otras preguntas

in one eighth of an hour ,ms.wolf can grade one third of a stack of papers how many hours will it take her to grade 2 stacks
which of the following equals 6,000,000 in scientific notation/
Counsuela is three times as old as Mary. In 10 years she will be only twice Mary's age. How old was Councuela 4 years ago?
either of the two resolutions are made by me. rewrite the sentence to make it correct
(a - b)(a 2 + ab + b 2)
Simplify 15.6 divided by negative 3..
if a wave has a velocity of 24 m/s and a period of 3.0 s. what is he frequency of the wave i
when charles darwin studied plants on the galapagos islands the naturalist realized that orchids had adapted to attract insects which word or phrase is the comp
who were the two leaders of the rebel army during the Mexican recolution
What is the value of x in the equation 3(2x + 8) = 0? –8 –4 4 8