In an examination, 70% students passed in Physics, 80% students passed in Chemistry, 75% students passed in Mathematics and 85% students passed in Biology, and x% students failed in all the four subjects. What is the minimum value of x ?
10
12
15
None of the above
2x2 + 3x - = 0 has roots - 2 and while the equation x2 - 3mx + 2m2 = 0 has both roots positive, where a > 0 and > 0. What is the value of ?
1
2
4
2x2 + 3x - = 0 has roots - 2 and while the equation x2 - 3mx + 2m2 = 0 has both roots positive, where a > 0 and > 0.
1
2
4
6
If c > 0 and 4a + c < 2b, then ax2 - bx + c = 0 has a root in which one of the following intervals ?
(0, 2)
(2, 3)
(3, 4)
( - 2, 0)
If ,where z = x + iy is a complex number, then which one of the following is corrcet ?
z = 1 + i
z = 1 - i
If both the roots of the equation x2 - 2kx + k2 - 4 = 0 lie between - 3 and 5, then which one of the following is correct ?
What is the number of distinct solutions of the equation (where z is a complex number) ?
One
Two
Three
Five
Which of the following are correct in respect of the system of equations x + y + z = 8, x - y + 2z = 6 and 3x - y + 5z = k ?
1. They have no solution, if k = 15.
2. They have infinitely many solutions, if k = 20
3. They have unique solution, if k = 25.
Select the correct answer using the code given below :
1 and 2 only
2 and 3 only
1 and 3 only
1, 2 and 3