f(x)=230x4+18x3+9x2−221x−9[−1,0],[0,1]
a)
a0=−1,b0=0f(a0)=f(−1)=230−18+9+221−9=433f(b0)=f(0)=−9p2=a0−f(b0)−f(a0)b0−a0f(a0)==−1−−9−4330+1⋅433=−0.0204a1=−0.0204,b1=0f(a1)=f(−0.0204)==230(−0.0204)4+18(−0.0204)3++9(−0.0204)2−221(−0.0204)−9=−4.488f(b1)=f(0)=−9p3=a1−f(b1)−f(a1)b1−a1f(a1)==−0.0204−−9+4.4880+0.0204⋅(−4.488)=−0.0408∣p3−p2∣=0.0204a2=−0.0408,b2=0f(a2)=f(−0.0408)==230(−0.0408)4+18(−0.0408)3++9(−0.0408)2−221(−0.0408)−9=0.034f(b2)=f(0)=−9p4=a2−f(b2)−f(a2)b2−a2f(a2)==−0.0408−−9−0.0340+0.0408⋅(0.034)=−0.0408∣p4−p3∣=0x=−0.0408
a0=0,b0=1f(a0)=f(0)=−9f(b0)=f(1)=230+18+9−221−9=27p2=a0−f(b0)−f(a0)b0−a0f(a0)==0−27+91−0⋅(−9)=0.25a1=0.25,b1=1f(a1)=f(0.25)==230(0.25)4+18(0.25)3++9(0.25)2−221(0.25)−9=−62.508f(b1)=f(1)=27p3=a1−f(b1)−f(a1)b1−a1f(a1)==0.25−27+62.5081−0.25⋅(−62.508)=0.771∣p3−p2∣=0.521a2=0.771,b2=1f(a2)=f(0.771)==230(0.771)4+18(0.771)3++9(0.771)2−221(0.771)−9=−84.519f(b2)=f(1)=27p4=a2−f(b2)−f(a2)b2−a2f(a2)==0.771−27+84.5191−0.771⋅(−84.519)=0.945∣p4−p3∣=0.174
a3=0.945,b3=1f(a3)=f(0.945)==230(0.945)4+18(0.945)3++9(0.945)2−221(0.945)−9=−11.194f(b3)=f(1)=27p5=a3−f(b3)−f(a3)b3−a3f(a3)==0.945−27+11.1941−0.945⋅(−11.194)=0.961∣p5−p4∣=0.016
a4=0.961,b4=1f(a4)=f(0.961)==230(0.961)4+18(0.961)3++9(0.961)2−221(0.961)−9=−0.929f(b4)=f(1)=27p6=a4−f(b4)−f(a4)b4−a4f(a4)==0.961−27+0.9291−0.961⋅(−0.929)=0.962∣p6−p5∣=0.001x=0.962
b)
f(x)=230x4+18x3+9x2−221x−9f′(x)=920x3+54x2+18x−221an+1=an−f′(an)f(an)a0=−1f(−1)=433f′(−1)=−920+54−18−221=−1105a1=a0−f′(a0)f(a0)=−1−−1105433=−0.608f(a1)=f(−0.608)==230(−0.608)4+18(−0.608)3++9(−0.608)2−221(−0.608)−9=156,079f′(a1)=f′(−0.608)==920(−0.608)3+54(−0.608)2++18(−0.608)−221=−418.757a2=a1−f′(a1)f(a1)=−0.608−−418.575156.079=−0.235∣a2−a1∣=0.373
f(a2)=f(−0.235)==230(−0.235)4+18(−0.235)3++9(−0.235)2−221(−0.235)−9=43.9f′(a2)=f′(−0.235)==920(−0.235)3+54(−0.235)2++18(−0.235)−221=−234.187a3=a2−f′(a2)f(a2)=−0.235−−234.18743.9=−0.0448∣a3−a2∣=0.19
f(a3)=f(−0.0448)==230(−0.0448)4+18(−0.0448)3++9(−0.0448)2−221(−0.0448)−9=0.918f′(a3)=f′(−0.0448)==920(−0.0448)3+54(−0.0448)2++18(−0.0448)−221=−221.78a4=a3−f′(a3)f(a3)=−0.0448−−221.780.918=−0.0401∣a4−a3∣=0.0047x=−0.0401
a0=1f(a0)=f(1)==230+18+9−221−9=27f′(a0)=f′(1)==920+54+18−221=771a1=a0−f′(a0)f(a0)=1−77127=0.965
f(a1)=f(0.965)==230(0.965)4+18(0.965)3++9(0.965)2−221(0.965)−9=1.743f′(a1)=f′(0.965)==920(0.965)3+54(0.965)2++18(0.965)−221=673.398a2=a1−f′(a1)f(a1)=0.965−673.3981.743=0.962∣a2−a1∣=0.003x=0.962
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