cos(2π/15) cos(4π/15) cos(8π/15) cos(14π/15) <span>
= cos(2π/15) cos(4π/15) cos(8π/15) cos(π – (π/15))
= cos(2π/15) cos(4π/15) cos(8π/15) * -cos(π/15)
= -cos(π/15) cos(2π/15) cos(4π/15) cos(8π/15)
= -16sin(π/15) cos(π/15) cos(2π/15) cos(4π/15) cos(8π/15) / [
16 sin(π/15) ]
= -8 * [ 2sin(π/15) cos(π/15) ] cos(2π/15) cos(4π/15)
cos(8π/15) / [ 16 sin(π/15) ]
= -8 sin(2π/15) cos(2π/15) cos(4π/15) cos(8π/15) / [ 16
sin(π/15) ]
= -4 * [ 2 sin(2π/15) cos(2π/15) ] cos(4π/15) cos(8π/15) / [
16 sin(π/15) ]
= -4 sin(4π/15) cos(4π/15) cos(8π/15) / [ 16 sin(π/15) ]
= -2 * [2 sin(4π/15) cos(4π/15) ] cos(8π/15) / [ 16 sin(π/15)
]
= -2 sin(8π/15) cos(8π/15) / [ 16 sin(π/15) ]
= -sin(16π/15) / [ 16 sin(π/15) ]
= -sin(π + π/15) / [ 16 sin(π/15) ]
= -1 * -sin(π/15) / [ 16 sin(π/15) ]
<span>= 1/16</span></span>
Answer:
I DON'T KNOW WHERE YOu belong because im in philippines
We know that formular for volume of pyramid=area of base ×height
the area of the base is 1/2×base×height
=1/2×15×14
=105cm²
the given volume is 270cm³
∴height=volume÷base area
=270cm³÷105cm²
=
=
I belive the answer is 24..
The bottom square portion would be 10 x 10 = 100 square inches.
The area of the triangle would be 1/2 x base x height.
The base is 10 - 6 = 4 inches.
The height is 16 -10 = 6 inches.
Area = 1/2 x 4 x 6 = 12 square inches.
Total area = 100 + 12 = 112 square inches.