For the following polynomial Px 2x4 3x2 3x 4 Evaluate P3
For the following polynomial P(x) = 2x^4 - 3x^2 + 3x - 4, Evaluate P(3) by using Horner\'s method.
Solution
P(x) = 2x4 - 3x2 + 3x - 4
= x( 2x3 - 3x1 + 3) - 4
= x ( x (( 2x2 - 3x )+ 3)) - 4
= x ( x (x( 2x - 3 )+ 3)) - 4
= x ( x (x(x( 2) - 3 )+ 3)) - 4
Also,we can use synthetic method
2 0 -3 3 -4
3
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2
Now multiply the number on the bottom and total as follows.
2 0 -3 3 -4
3 6 18 45 144
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2 6 15 48 140
We have f(3)=32. Let\'s run a check
f(3)=2*8139+3*34=.140
