sin^4 pi/24 + cos^4 pi/24+cos^4 5pi/24 + sin^4 5pi/24

=sin^4(p/24)+2sin(p/24)cos(p/24)+cos^4(p/24)+cos^4(5p/24)+2sin(5p/24)cos(5p/24)+sin^4(p/24) - 2sin(p/24)cos(p/24) - 2sin(5p/24)cos(5p/24) = (sin(p/24) + cos(p/24)) + (sin(5p/24) + cos(5p/24)) - 2sin(p/24)cos(p/24) - 2sin(5p/24)cos(5p/24) =1 + 1 - 2sin(p/24)cos(p/24) - 2sin(5p/24)cos(5p/24) = 2 - 0.5 * 4sin(p/24)cos(p/24) - 0.5 * 4sin(5p/24)cos(5p/24) = 2 - 0.5 * sin(p/12) - 0.5 * sin(5p/12) =2 - 0.5 * (sin(p/12) + sin(5p/12)) = 2 - 0.25 * (1 - cos(p/6) + 1 - cos(5p/6) ) = 2 - 0.25 * (1 - 3/2 + 1 +3/2 ) = 2 - 0.25 * (1 + 1 ) = 1.5