Question

Решите уравнения (1-у)^3+8у=7+у^2(3-у)

Answer 1

(1-y)³+8y=7+y²(3-y)  

1-3y+3y²-y³+8y   =  7+3y²-y³

5y=7-1

5y=6

y=6/5  =  1  1/5