If the polynomial 2x³ + 3x² - 2x - 3 is completely divisible by (2x + a), and the quotient is equal to (x² - 1), then one of the values of a is :

1. -3

2. -1

3. 1

4. 3

A polynomial in x is x³ + 5x² - kx - 24. Which of the following is a factor of the given polynomial so that the value of k is 2?

1. (x + 2)

2. (x - 3)

3. (x + 4)

4. (x - 4)

If the sum of n terms of an arithmetic progression S_n = n² - n, then the third term of the series is :

1. 2

2. 4

3. 6

4. 9