总述:本次共解1题。其中
☆算术计算1题
〖1/1算式〗
作业:求算式 (4*(cos(2*π/7))^2)*(4*(cos(4*π/7)))^2*(4*(cos(8*π/7))^2) 的值.
题型:数学计算
解:
(4*(cos(2*π/7))^2)*(4*(cos(4*π/7)))^2*(4*(cos(8*π/7))^2)
=(4*(cos0.897598)^2)*(4*(cos(4*π/7)))^2*(4*(cos(8*π/7))^2)
=(4*0.62349^2)*(4*(cos(4*π/7)))^2*(4*(cos(8*π/7))^2)
=1.554959*(4*(cos(4*π/7)))^2*(4*(cos(8*π/7))^2)
=1.554959*(4*(cos1.795196))^2*(4*(cos(8*π/7))^2)
=1.554959*(4*(-0.222521))^2*(4*(cos(8*π/7))^2)
=1.554959*(-0.890084)^2*(4*(cos(8*π/7))^2)
=1.554959*(-0.890084)^2*(4*(cos3.590392)^2)
=1.554959*(-0.890084)^2*(4*(-0.900969)^2)
=1.554959*(-0.890084)^2*3.246981
=1.554959*0.792249527056*3.246981
=1.231916*3.246981
=4.000008 答案:(4*(cos(2*π/7))^2)*(4*(cos(4*π/7)))^2*(4*(cos(8*π/7))^2)=4.000008 注:弧度制你的问题在这里没有得到解决?请到 热门难题 里面看看吧!