用秦九韶算法求f(x)=12-8x^2+6x^4+5x^5+3x^6.用x=4时,v4的值

f(x)=12-8x^2+6x^4+5x^5+3x^6
=3x^6+5x^5+6x^4-8x^2+12
=(((3x+5)x+6)x^2-8)x^2+12
V4=((3x+5)x+6)x^2-8
x=4代入得:
v4=1176