PUMPA - SMART LEARNING
எங்கள் ஆசிரியர்களுடன் 1-ஆன்-1 ஆலோசனை நேரத்தைப் பெறுங்கள். டாப்பர் ஆவதற்கு நாங்கள் பயிற்சி அளிப்போம்
Book Free Demo1. Find the discriminant of the quadratic equation \(2x^2 + 7x - 4 = 0\), and hence find the nature of its roots.
Solution:
The given equation is \(2x^2 + 7x - 4 = 0\).
Here, \(a = 2\), \(b = 7\) and \(c = -4\).
Discriminant \(=\) \(b^2 - 4ac\)
\(=\) \(7^2 - 4(2)(-4)\)
\(=\) \(49 + 32\)
\(=\) \(81 > 0\)
Thus, the equation has real and distinct roots.
2. Find the discriminant of the quadratic equation \(x^2 - 8x + 16 = 0\), and hence find the nature of its roots.
Solution:
The given equation is \(x^2 - 8x + 16 = 0\).
Here, \(a = 1\), \(b = -8\) and \(c = 16\).
Discriminant \(=\) \(b^2 - 4ac\)
\(=\) \((-8)^2 - 4(1)(16)\)
\(=\) \(64 - 64\)
\(=\) \(0\)
Thus, the equation has real and equal roots.
3. Find the discriminant of the quadratic equation \(x^2 - 5x + 12 = 0\), and hence find the nature of its roots.
Solution:
The given equation is \(x^2 - 5x + 12 = 0\).
Here, \(a = 1\), \(b = -5\) and \(c = 12\).
Discriminant \(=\) \(b^2 - 4ac\)
\(=\) \((-5)^2 - 4(1)(12)\)
\(=\) \(25 - 48\)
\(=\) \(-23 < 0\)
Thus, the equation has no real roots.