Mathematics - Online Test
Q1.
If the sides of a triangle be 2x + 1, - 1 and +x +1, then the greatest angle is
Answer : Option D
Explaination / Solution:
Q2. The area enclosed by the curve is equal to
Answer : Option A
Explaination / Solution:
The area of the standard ellipse is given by ;πab. Here , a = 5 and b = 4 Therefore , the area of curve is π(5)(4)=20π.
Q3. In three dimensional space, locus of the equation is
Answer : Option D
Explaination / Solution:
No Explaination.
Q4.
If A and B are invertible matrices of the same order, then is equal to
Answer : Option C
Explaination / Solution:
By the property of inverse is equal to .
Q5. Let f (x) = x – cos x, x∈R, then f is
Answer : Option D
Explaination / Solution:
Hence an increasing function.
Q6.
If is a cube root of unity , then upto 2n factors is
Answer : Option A
Explaination / Solution:
Q7. If A ⊆B , then A∩B is equal to
Answer : Option D
Explaination / Solution:
A ⊆B means Set A is contained in the set B.So common region is The Set A
Q8. The value of the determinant 
Answer : Option A
Explaination / Solution:
expanding along R1
Q9. The coefficient of in the expansion of is
Answer : Option D
Explaination / Solution:
Q10. Find all pairs of consecutive odd natural numbers, both of which are larger than 10, such that their sum is less than 40.
Answer : Option B
Explaination / Solution:
Let the consecutive odd natural numbers be x and x+2.
According to the question , x>10 and
Now
Hence the maximum value of x is 17 and minimum value is 11.
So the possible pairs of odd natural numbers are ( 11 , 13 ) , ( 13 , 15 ) , ( 15 , 17 ) , ( 17 , 19 )
