+0

Find the value of a and b so that the polynomial x3 – 4x2 + ax + b is exactly divisible by x – 2 as well as x + 1.

0
139
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Find the value of a and b so that the polynomial x3 – 4x2 + ax + b is exactly divisible by x – 2 as well as x + 1.

May 27, 2019

#1
+104488
+2

Find the value of a and b so that the polynomial x3 – 4x2 + ax + b is exactly divisible by x – 2 as well as x + 1.

$$f(x)=x^3-4x^2+ax+b\\ f(2)=8-16+2a+b=0\\ \qquad 2a+b=8 \qquad(1)\\ f(-1)=-1-4-a+b=0\\ \qquad -a+b=5 \qquad(2)$$

Now solve equations 1 and 2 simultaneously.

Guest if you do not understand then say what it is that you do not understand.  (and someone will help you further)

May 27, 2019
edited by Melody  May 27, 2019
#2
-1