Engineering Board Exam Reviewer · Polynomials: Remainder and Factor Theorems · medium

Find the sum of the roots of 2x3-5x2+3x-8=0.

1. -2.5
2. 2.5
3. 1.5
4. 4

Answer

B. 2.5

Solution

For ax3+bx2+cx+d=0 the sum of the roots is - ba=--5/2=2.5.

More Polynomials: Remainder and Factor Theorems questions

1. Use synthetic division to find the quotient when 2x3-3x2+5x-7 is divided by x-2.
2. When x3+ax+7 is divided by x+2 the remainder is -3. Find a.
3. Find all roots of x3-3x2-4x+12=0.
4. Find k so that x-2 is a factor of x2+kx-10.
5. Find the remainder when x3-2x2+4x-5 is divided by x-2.
6. The roots of x3-6x2+kx-6=0 are in arithmetic progression. Find k.
7. Find the remainder when 2x101+3x100-5 is divided by x+1.
8. If x-1 and x+2 are both factors of x3+px2+qx-6, find pq.
9. Find the monic polynomial of lowest degree whose roots are 1, -2, and 3.

All Polynomials: Remainder and Factor Theorems questions