Question

EXI
1. Find the roots of the following
completing the square:
0 2r-7x+3 = 0
(iii) 4x2 +413x + 3 = 0
2. Find the roots of the quadratic
formula.​

Answer 1

Answer:

It should be:

4x² + 13x + 3 = 0

By the method of completing the square:

4x² + 13x + 3 = 0

=> x² + 13x/4 + 3/4 = 0

=> (x + 13/8)² -(13/8)² + 3/4 = 0

=> (x + 13/8)² - 169/64 + 3/4 = 0

=> (x + 13/8)² -(169 - 48/64) = 0

=> (x + 13/8)² - 121/64 = 0

=> (x + 13/8)² = 121/64

=> x - 13/8 = ±$\sqrt {121/64}$

=> x + 13/8 = ±11/8

=> x = ±11/8 - 13/8

=> x = 11/8 - 13/8 or -11/8 - 13/8

=> x = -2/8 or -24/8

=> x = -1/4 or -3