Question

Y乘(Y+1)乘(Y+2)乘(Y+3)=360.

Answer 1

y*(y+1)*(y+2)*(y+3)=360

(y^2+3y)*(y^2+3y+2)=360

设y^2+3y=x

则x*(x+2)=360

x^2+2x-360=0

(x-18)*(x+20)=0

x=18或-20

因为y>0

所以y^2+3y=18

y^2+3y-18=0

(y-3)*(y+6)=0

所以y=3或-6