若sinx+sin^2x=1,则cos^2x+cos^4x=?

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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