Mathematics - Online Test

Q1. , where a > 0, is equal to
Answer : Option D
Explaination / Solution:

letx=1t;Ltt0at1t=lna
Q2. If two corner points of the feasible region are both optimal solutions of the same type, i.e., both produce the same maximum or minimum.
Answer : Option D
Explaination / Solution:

If two corner points of the feasible region are both optimal solutions of the same type, i.e., both produce the same maximum or minimum , then any point on the line segment joining these two points is also an optimal solution of the same type .

Q3. If x, y, z are in A.P., then (x + 2y – z) (x + z – y) (z + 2y – x) is equal to
Answer : Option B
Explaination / Solution:



Q4. The coefficient of correlation r satisfies
Answer : Option D
Explaination / Solution:

r can't be numerically more than 1

Q5. Let A = {1, 2, 3, 4, 5, 6}. Which of the following partitions of A correspond to an equivalence relation on A?
Answer : Option B
Explaination / Solution:

Conditions for the partition sub-sets to be an equivalence relation:

(i) The partition sub-sets must be disjoint i.e.their is no common elements between them

(ii) Their union must be equal to the main set (super-set)

Here the set A={1,2,3,4,5,6},the partition sub-sets {1,3},{2,4,5},{6} are pairwise disjoint and their union i.e. {1,3} U {2,4,5} U {6} = {1,2,3,4,5,6} = A,which is the condition for  the partition sub-sets to be an equivalence relation of the set A.


Q6. The value of the determinant 
Answer : Option B
Explaination / Solution:

since C1 And C2 are identical

=(a+b+c)x0 =0


Q7. The straight lines x + y - 4 = 0 , 3x + y – 4 = 0 , x - 3y – 4 = 0 form a triangle which is
Answer : Option A
Explaination / Solution:

The triangle formed by these lines is a right angled triangle

If the lines are perpendicular to each other, then the product of their slopes is -1

The slope of lines  3x + y – 4 = 0 , x - 3y – 4 = 0 are  -3 and 1/3 respectively.

The product of the slopes is -1

Hence these two lines are perpendicular to each other

This infers that the triangle formed by these lines is a right angled triangle.


Q8. Let p and q be two propositions. Then, the contrapositive of the implication p→q is
Answer : Option B
Explaination / Solution:

the contrapositve of p→q is∼q→∼p

Q9.  is equal to
Answer : Option B
Explaination / Solution:

ddx(f(x)dx)=f(x)
Q10. for vector addition which of the following is correct?
Answer : Option A
Explaination / Solution:

Addition of two vectors i.e. vector addition is associative. i.e.