Polynomials (roots) (1 Viewer)

[senarillosk]

Two of the roots of x³ - px² - qx - 4 = 0 are 3 and 5.

a.) Find the other root.
b.) Find p and q


Need help on this question. Thank you.

 

[leehuan]

The short version:

a) Use product of roots 3*5*alpha=4
b) Use some of one root at a time to find p, use some of two roots at a time to find q

Note that for roots alpha beta gamma, beta = 3 and gamma = 5