因为(sinα+cosα)=1
所以(sinα+cosα)^2=1
那么sin^α+2sinαcosα+cos^α=1
因为sin^α+cos^α=1
所以sinα·cosα=0
若sin(π-α)+cos(2π-α)＝1 ,则sin4α+cos4α+sin(π+α)·cos(4π-α)的值为___
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