(0.3—x)X(500+1000x)=120怎样解?
问题描述:
(0.3—x)X(500+1000x)=120怎样解?
答
其中[2]用来表示二次平方(0.3—x)X(500+1000x)=1200.3X500+0.3X1000x-500x-1000x[2]=120150+300x-500x-1000x[2]=12030-200x-1000x[2]=01000x[2]+200x-30=0100x[2]+20x-3=0(10x)[2]+2X1X10x+1-4=0(10x+1)[2]=410x+1=...