Resposta :
X= 1000(4+3p+p²)
X'p= 1000(3+2p)
X'(0,90)= 1000(3+2.0,90)
X'(0,90)= 1000(3+1,8)
X'(0,90)= 1000.4,8
X'(0,90)= 48000
X'p= 1000(3+2p)
X'(0,90)= 1000(3+2.0,90)
X'(0,90)= 1000(3+1,8)
X'(0,90)= 1000.4,8
X'(0,90)= 48000