The adjacent sides of a rectangle are x2−4xy+7y2 and x3−5xy2.Find its area.
Reqd.area=(x2−4xy+7y2)(x3−5xy2)=x2(x3−5xy2)−4xy(x3−5xy2)+7y2(x3−5xy2)=x5−5x3y2−4x4y+20x2y3+7x3y2−35xy4=x5+(7−5)x3y2−4x4y+20x2y3−35xy4=x5+2x3y2−4x4y+20x2y3−35xy4=(x5−4x4y+2x3y2+20x2y3−35xy4) sq.unit.