若sinx+sin^2x=1,则cos^2x+cos^4x=?
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/18 08:02:40
![若sinx+sin^2x=1,则cos^2x+cos^4x=?](/uploads/image/z/5629707-27-7.jpg?t=%E8%8B%A5sinx%2Bsin%5E2x%3D1%2C%E5%88%99cos%5E2x%2Bcos%5E4x%3D%3F)
x){ѽ83BHU<혙_dk(
[{"}o)PE5ԅC%Q@e5!M(B0/.H̳nz:g]?]:u6<ٽ
@P9 # ,>
若sinx+sin^2x=1,则cos^2x+cos^4x=?
若sinx+sin^2x=1,则cos^2x+cos^4x=?
若sinx+sin^2x=1,则cos^2x+cos^4x=?
由 sinx+sin^2x=1
得 sinx=1-sin^2x=cos^2x
cos^2x+cos^4x
=cos^2x(1+cos^2x)
=sinx(1+sinx)
=sinx+sin^2x
=1
由 sinx+sin^2x=1
得 sinx=1-sin^2x=cos^2x
cos^2x+cos^4x
=cos^2x(1+cos^2x)
=sinx(1+sinx)
=sinx+sin^2x
=1
在线指导
由sinx+sin^2x=1
得sinx=1-sin^2x=cos^2x
所以cos^2x+cos^4x
= cos^2x(1+cos^2x)
= sinx(sinx+1)
= sin^2x+sinx
= 1