Question

find the reminder when a x cube minus b x square minus x plus 5 and x cube + 8 square + 2 x minus b minus 4 are divided by (X + 1) are - 3 and 20 respectively find a and b

Answer 1

ax³ - bx² - x + 5 = -3

x = -1

-a - b - 1 + 5 = -3

-a - b = -3 - 6

-a - b = -9      -----------(1)

x³ + 8² + 2x - b = 20

-1 + 64 + -2 - b = 20

-b = 20 - 61

b = 39

Apply on (1)

-a - b = -9

-a - 39 = -9

a = 9 - 39

a = -30