sin(π/4+α)sin(π/4-α)=1/6,α∈(0.π/2),求:sin4α的值
来源:学生作业帮助网 编辑:作业帮 时间:2024/08/03 18:30:13
![sin(π/4+α)sin(π/4-α)=1/6,α∈(0.π/2),求:sin4α的值](/uploads/image/z/10145417-41-7.jpg?t=sin%28%CF%80%2F4%2B%CE%B1%29sin%EF%BC%88%CF%80%2F4-%CE%B1%EF%BC%89%3D1%2F6%2C%CE%B1%E2%88%88%EF%BC%880.%CF%80%2F2%EF%BC%89%2C%E6%B1%82%EF%BC%9Asin4%CE%B1%E7%9A%84%E5%80%BC)
x)+8ߠo}n&~O{n=f:6>
%:663Z6I*ҧIv64tMitr~1HHSAW6JB0 n0&
00z`Fql4PZHA2/.H̳y >
sin(π/4+α)sin(π/4-α)=1/6,α∈(0.π/2),求:sin4α的值
sin(π/4+α)sin(π/4-α)=1/6,α∈(0.π/2),求:sin4α的值
sin(π/4+α)sin(π/4-α)=1/6,α∈(0.π/2),求:sin4α的值
sin(π/4+α)sin(π/4-α)
=-0.5[cos(π/2) --cos(2α)]
=0.5cos(2α)
=1/6
cos(2α)=1/3
sin(2α)=2根号2/3
sin4α=2sin2α*cos2α
=4根号2/9