Question

For what value of a is 2x^3+9x^2+11x+a+3 exactly divisible by 2x-1

Answer 1

just make both divisor and dividend 0 and get value of a

Answer 2

Hey there!

2x - 1 = 0
x = 1/2

2x³ + 9x² + 11x + a + 3
2(1/2)³ + 9(1/2)² + 11(1/2) + a + 3 = 0
2*1/8 + 9*1/4 + 11*1/2 + a + 3 =0
1/4 + 9/4 + 11/2 + 3 + a = 0
Now take LCM ( 4 and 2) = 4
1 + 9 + 22 + 12 + 4a/ 4 = 0
44 + 4a / 4 = 0
44 + 4a = 0
4a = - 44
a = - 11

Hope it help