sin²β+cos^4+sin²βcos²β为多少,怎么算

问题描述:

sin²β+cos^4+sin²βcos²β为多少,怎么算

因为sin²β+cos²β=1,所以sin²β=1-cos²β
sin²β+cos^4+sin²βcos²β
=1-cos²β+cos^4β+(1-cos²β)cos²β
=1-cos²β+cos^4β+cos²β-cos^4β
=1