ANSWER: f(4)=369,f′(4)=344
EXPLANATION:
f(x)=a4x4+a3x3+a2x2+a1x+a0=x4+2x3−x2+1
To calculate f(4) , we represent the polynomial f in the form f(x)=(x−4)(b3x3+b2x2+b1x+b0)+r , using the Horner's method.
b3=a4,bk−1=4bk+ak,k=3,2,1,r=4b0+a0
Thus, we obtain b3=1→b2=4⋅1+2=6→b1=4⋅6−1=23→
→b0=4⋅23+0=→r=4⋅92+1=369,r=f(4)
Similarly: f′(x)=4x3+6x2−2x =a3x3+a2x2+a1x+a0= =(x−4)(b2x2+b1x+b0)+r
b2=4→b1=4⋅4+6=22→b0=4⋅22−2=86→
=→r=4⋅86+0=344,r=f′(4)=344
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