Find the constant of a cubic function

Hi, everyone, I have a cubic function of the form: A*x + B*x**3. At x = 1, this function corresponds to y = 0.845, and at x = 0 it corresponds to y = 0. How can I determine the constants A and B? Thank you for any explanation.

Answer 1

[Torsten]

All cubics of the above form with

A+B=0.845

have

f(0)=0 and f(1)=0.845.

A and B are not uniquely determined by your two conditions.The first (f(0)=0) is automatically satisfied because of the form of your cubic.

Best wishes

Torsten.

[Mma Kenya]

Thank you Torsten !!!