Réponse:
1)
F(x) = x - ½x² + ⅓x³-¼x⁴+k
et F(1) = 0
1-½+⅓-¼+k = 0
k = -7/12
F(x) = x - ½x² + ⅓x³-¼x⁴-7/12
2)
F(x) = ½x²-1/x-2√x + k
et F(1)=1
½-1-2+k = 1
k=7/2
F(x)= ½x²-1/x-2√x + 7/2
