If a and b are the roots of the quadratic equation x2 + px + 12 = 0 wi

1.	If a and b are the roots of the quadratic equation x2 + px + 12 = 0 with the condition a - b = 1, then the value of 'p' is ......(A) 1(B) 7(C) -7(D) 7 or -7
Answer» The correct option is: (D) 7 or -7 Explanation: Given equation is x² + px + 12 = 0 Now, if a and b are its roois, then sum of roots, 6 + b = -p and product of roots, a x b = 12 Also,a - b = 1 (Given) We know that, (a - b)² = (a + b)² - 4ab => 1 = p² - 4 x 12 => 1 = p² - 48 => p² = 49 = p = ±7

If a and b are the roots of the quadratic equation x2 + px + 12 = 0 with the condition a - b = 1, then the value of 'p' is ......(A) 1(B) 7(C) -7(D) 7 or -7

Answer»

The correct option is: (D) 7 or -7

Explanation:

Given equation is x² + px + 12 = 0

Now, if a and b are its roois, then

sum of roots, 6 + b = -p and

product of roots, a x b = 12

Also,a - b = 1 (Given)

We know that, (a - b)² = (a + b)² - 4ab

=> 1 = p² - 4 x 12 => 1 = p² - 48 => p² = 49 = p = ±7