把函数化为一般式(y=ax^2+bx+c)
①y=(400-x)(8+四分之五十x)
②:Y=(X-50)(1000-10x
把函数化为一般式(y=ax^2+bx+c)
①y=(400-x)(8+四分之五十x)
②:Y=(X-50)(1000-10x
1
y=(400-x)(8+50x/4)
=3200+5000x-8x-50x^2/4
=(-25/2)x^2+4992x+3200
2
y=(x-5)(1000-10x)
=1000x-10x^2-5000+50x
=-10x^2+1050x-5000