Mathematics - Online Test

Q1. If  is equal to
Answer : Option A
Explaination / Solution:

secθ+ tanθsecθtanθ=1cosθ+sinθcosθ1cosθsinθcosθ=1+sinθ1sinθ=1+35135=4
Q2. If [x] stands for the integral part of x, then
Answer : Option D
Explaination / Solution:

The is defined as the value which takes the nearest small integer in every integer interval . For example in the interval  the value of the function is 0 since it is the lowest integer in that interval . Hence which gives the value as 1,which is the lowest integer of that interval.

Q3. The smallest +ve integer n , for which  n!< holds is
Answer : Option A
Explaination / Solution:

when n = 2 ,  L H S  :  n ! = 2 ! = 2x1 = 2    RHS: 

But if n = 1 , the inequation does not hold good.


Q4.

The equation represents


Answer : Option C
Explaination / Solution:

The general equation of the circle is x2+y2-2gh-2fy+c = 0. Sice the given equations satisfies the general equation, it represents the equation of the circle.

 


Q5. The number of selections of n different things taken r at a time which exclude m particular things is
Answer : Option A
Explaination / Solution:

No: of combinations of n different things taken r at at a time is given by nCr

No: of combinations of n different things taken r at a time and excluding m particular things is n - mC= C(n-m,r)


Q6. The order of the equation = 0 is
Answer : Option B
Explaination / Solution:

Since the highest derivative term is  hence the order is 3.

Q7. If l, m, n are the direction cosines and a, b, c are the direction ratios of a line then
Answer : Option D
Explaination / Solution:

using direction ratio a,b,c we got a vector  along  the line ,for direction cosine find  unit vector then  where l,m,n represent direction cosine

Q8.

In a , (b +c) cos A + (c + a) cos B + (a + b) cos C is equal to


Answer : Option B
Explaination / Solution:



Q9. AOB is the positive quadrant of the ellipse  in which OA = a and OB = b . The area between the arc AB and chord AB of the ellipse is
Answer : Option B
Explaination / Solution:

Required area :
 area of ellipse – area of right angled triangle AOB. 
= ab –  ab =  ( - 2 ) .

Q10. The two vectors [1,1,1] and [1, a, a2], where a = , are
Answer : Option B
Explaination / Solution:

Dot product of two vectors = 1 + a + a= 0
 So orthogonal