Notifications
Clear all
Find the roots of the following quadratic equations, if they exist, by the method of completing the square: (i) 4x^2 + 4√3x + 3 = 0 (ii) 2x^2 + x + 4 = 0
Quadratic Equations
1
Posts
2
Users
0
Likes
469
Views
0
30/05/2021 10:42 am
Topic starter
Find the roots of the following quadratic equations, if they exist, by the method of completing the square:
(i) 4x2 + 4√3x + 3 = 0
(ii) 2x2 + x + 4 = 0
Answer
Add a comment
Add a comment
Topic Tags
1 Answer
0
30/05/2021 10:44 am
(i) 4x2 + 4√3x + 3 = 0
Converting the equation into a2+2ab+b2 form, we get,
⇒ (2x)2 + 2 × 2x × √3 + (√3)2 = 0
⇒ (2x + √3)2 = 0
⇒ (2x + √3) = 0 and (2x + √3) = 0
Therefore, either x = -√3/2 or x = -√3/2.
(ii) 2x2 + x + 4 = 0
⇒ 2x2 + x = -4
Dividing both sides of the equation by 2, we get
⇒ x2 + 1/2x = 2
⇒ x2 + 2 × x × 1/4 = -2
By adding (1/4)2 to both sides of the equation, we get
⇒ (x)2 + 2 × x × 1/4 + (1/4)2 = (1/4)2 – 2
⇒ (x + 1/4)2 = 1/16 – 2
⇒ (x + 1/4)2 = -31/16
The square of numbers cannot be negative.
Therefore, there is no real root for the given equation, 2x2 + x + 4 = 0.
Add a comment
Add a comment
Forum Jump:
Related Topics
-
Is it possible to design a rectangular park of perimeter 80 and area 400 m^2? If so find its length and breadth.
4 years ago
-
Is the following situation possible? If so, determine their present ages. The sum of the ages of two friends is 20 years. Four years ago, the product of their ages in years was 48.
4 years ago
-
Is it possible to design a rectangular mango grove whose length is twice its breadth, and the area is 800 m^2? If so, find its length and breadth.
4 years ago
-
Find the values of k for each of the following quadratic equations, so that they have two equal roots. (i) 2x^2 + kx + 3 = 0 (ii) kx (x – 2) + 6 = 0
4 years ago
-
Find the nature of the roots of the following quadratic equations. If the real roots exist, find them; 2x^2 – 6x + 3 = 0
4 years ago
Forum Information
- 321 Forums
- 27.3 K Topics
- 53.8 K Posts
- 4 Online
- 12.4 K Members
Our newest member: Stripchat
Forum Icons:
Forum contains no unread posts
Forum contains unread posts
Topic Icons:
Not Replied
Replied
Active
Hot
Sticky
Unapproved
Solved
Private
Closed