Advertisements
Advertisements
Question
Find the discriminant of the following equations and hence find the nature of roots: 2x2 + 15x + 30 = 0
Solution
2x2 + 15x + 30 = 0
Here a = 2, b = 15, c = 30
∴ D = b2 - 4ac
= (15)2 - 4 x 2 x 30
= 225 - 240
= -15
∴ Discriminant = -15
∵ D < 0
∴ Root are not real.
APPEARS IN
RELATED QUESTIONS
Find the values of k for which the quadratic equation (k + 4) x2 + (k + 1) x + 1 = 0 has equal roots. Also find these roots.
If (k – 3), (2k + l) and (4k + 3) are three consecutive terms of an A.P., find the value of k.
Find the values of k for which the roots are real and equal in each of the following equation:
x2 - 2(5 + 2k)x + 3(7 + 10k) = 0
Find the value of the discriminant in the following quadratic equation:
2x2 - 3x + 1 = O
Determine the nature of the roots of the following quadratic equation :
2x2 + 5x - 6 = 0
If `sqrt(2)` is a root of the equation `"k"x^2 + sqrt(2x) - 4` = 0, find the value of k.
Choose the correct answer from the given four options :
Which of the following equations has two distinct real roots?
If b = 0, c < 0, is it true that the roots of x2 + bx + c = 0 are numerically equal and opposite in sign? Justify.
Find the value of k for which the roots of the quadratic equation 5x2 – 10x + k = 0 are real and equal.
The roots of equation (q – r)x2 + (r – p)x + (p – q) = 0 are equal. Prove that: 2q = p + r, that is, p, q and r are in A.P.
