問題詳情:
已知多項式x4-y+3xy-2xy2-5x3y3-1,按要求解答下列問題: (1)指出該多項式的項; (2)該多項式的次數是______,三次項的係數是______. (3)按y的降冪排列爲:______. (4)若|x+1|+|y-2|=0,試求該多項式的值.
【回答】
(1)該多項式的項爲:x4,y,3xy,-2xy2,-5x3y3,-1;
(2)該多項式的次數是6,三次項的係數是-2; 故*爲:6,-2;
(3)按y的降冪排列爲:-5x3y3-2xy2-y+3xy+x4-1; 故*爲:-5x3y3-2xy2-y+3xy+x4-1; (4)∵|x+1|+|y-2|=0, ∴x=-1,y=2, ∴x4-y+3xy-2xy2-5x3y3-1=(-1)4-2+3×(-1)×2-2(-1)×22-5(-1)3×23-1=1-2-6+8+40-1=40.
知識點:整式的加減
題型:解答題