Question

Find f. (Use C for the constant of the first antiderivative and D for the constant of the second antiderivative.)
f ''(x) = 4 + x^3 + x^6
i got Cx+D+2x^2+(x^5)/5+(x^8)/8 is this correct?

Answer 1

\[f'(x) = \int\limits (4+x^3+x^6) dx = 4x+\frac{ x^4 }{ 4 }+\frac{ x^7 }{ 7 } + C\]
\[f(x) = \int\limits (4x+\frac{ x^4 }{ 4 }+\frac{ x^7 }{ 7 }+C) dx = \frac{ 4x^2 }{ 2 }+\frac{ x^5 }{ 20 }+\frac{ x^8 }{ 56 }+Cx+D\]

Answer 2

See your mistake?

Answer 3

oh I see it thanks!!

Answer 4

Np :)