If (x - 1) is a factor of p(x) = ax^3 + bx^2 - 5x + 2 and p(2) = 0 as well, set up the two equations. From p(1) = 0 you get a + b = 3, and from p(2) = 0 you get 8a + 4b = 8. Find the value of a.

Question

Accepted Answer

-1. From a + b = 3 and 8a + 4b = 8 (i.e. 2a + b = 2). Subtract: (2a + b) - (a + b) = 2 - 3 gives a = -1. Then b = 4.

If $(x - 1)$ is a factor of $p (x) = a x^{3} + b x^{2} - 5 x + 2$ and $p (2) = 0$ as well, set up the two equations.
From $p (1) = 0$ you get $a + b = 3$ , and from $p (2) = 0$ you get $8 a + 4 b = 8$ .
Find the value of a.

Step-by-Step Solution

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More Class 9 Factor Theorem and Factorisation practice

If (x−1) is a factor of p(x)=ax3+bx2−5x+2 and p(2)=0 as well, set up the two equations.From p(1)=0 you get a+b=3, and from p(2)=0 you get 8a+4b=8.Find the value of a.

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 9 Factor Theorem and Factorisation practice

If $(x - 1)$ is a factor of $p (x) = a x^{3} + b x^{2} - 5 x + 2$ and $p (2) = 0$ as well, set up the two equations.
From $p (1) = 0$ you get $a + b = 3$ , and from $p (2) = 0$ you get $8 a + 4 b = 8$ .
Find the value of a.