Two graphs have gradient functions dy/dx = 3x^2+3x+a and dy/dx = 3x^2-2x+1.

[frz17]

Hey, I am struggling and I need a help please !
I tried to do it but I am sure that's completly wrong ....

1. Two graphs have gradient functions dy/dx = 3x^2+3x+a and dy/dx = 3x^2-2x+1. The graphs cross at the point (1, a) and also at the point where x=-2.
Find the equations of the two graphs, and the value of a.

 

[Deleted member 4993]

Hey, I am struggling and I need a help please !
I tried to do it but I am sure that's completly wrong ....

1. Two graphs have gradient functions dy/dx = 3x^2+3x+a and dy/dx = 3x^2-2x+1. The graphs cross at the point (1, a) and also at the point where x=-2.
Find the equations of the two graphs, and the value of a.

First thing I would do is to integrate those to given functions:

f₁(x) = \(\displaystyle \displaystyle{\int {(3x^2+3x+a)} \ \ dx}\)

f₂(x) = \(\displaystyle \displaystyle{\int {(3x^2-2x+1)} \ \ dx}\)

Did you do that?

What did you get?