化简:-p²cos180°+qsin9°-2pqcos0°
问题描述:
化简:-p²cos180°+qsin9°-2pqcos0°
化简-p²cos180°+qsin9°-2pqcos0°
答
-p²cos180°+qsin9°-2pqcos0°?
是不是-p²cos180°+qsin90°-2pqcos0°
-p²cos180°+qsin90°-2pqcos0°
=-p²*(-1)+q*1-2pq*1
=p²+q-2pq