Exercise 2:3 Questions 3-5

3. Determine for which of the following equations there are (i) Two unequal 'real' roots, (ii) Equal roots or (iii) No 'real' roots.

(a) 3x² + 3x - 4 = 0          (b) 6x² +3x +4 = 0        (c) 2x² - 3x - 1 = 0         (d) 2.5x² + 4x +1 = 0        (e) 3.5x² + 7.5x + 4 = 0        (f) 4a²x² + 4abx + b² = 0

4. Find the value of a if the equation (2a-1)x² -2ax + 1 = 0 has equal roots. Solve the equation for that single value of x. 

5. Show that if there are no real roots of the quadratic equation (2b +1)x² -3bx + b = 0 then b²-4b is negative.

Can anyone please help me answer these questions????????