y=cos^2x-sin^2x+2sinxcosx(x属于R)的值域为什么
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/27 04:50:48
![y=cos^2x-sin^2x+2sinxcosx(x属于R)的值域为什么](/uploads/image/z/9293617-1-7.jpg?t=y%3Dcos%5E2x-sin%5E2x%2B2sinxcosx%28x%E5%B1%9E%E4%BA%8ER%29%E7%9A%84%E5%80%BC%E5%9F%9F%E4%B8%BA%E4%BB%80%E4%B9%88)
y=cos^2x-sin^2x+2sinxcosx(x属于R)的值域为什么
y=cos^2x-sin^2x+2sinxcosx(x属于R)的值域为什么
y=cos^2x-sin^2x+2sinxcosx(x属于R)的值域为什么
y=cos^2x-sin^2x+2sinxcosx
=(cosx)^2-(sinx)^2+2sinxcosx
=cos2x+sin2x
=√2sin(2x+π/4)
√2≤y≤√2